Rolls-Royce Archives
| Identifier | Entry | ||
| img001 | Introductory memo about a series of reports on car performance to help officials handle customer complaints. | ||
| View original record | FUNDAMENTALS OF CAR PERFORMANCE. OBJECT OF MEMOS. The object of these notes is to assist Depots and Officials who are away from the Works to deal with criticisms or complaints. The information… | ||
| img002 | Index of various car performance and mechanical topics. | ||
| View original record | I N D E X (1) FUNDAMENTALS OF CAR PERFORMANCE. Acceleration. Tractive resistance. Hill climbing. High speed performance. (2) WIND RESISTANCE. (3) THE COOLING SYSTEM. (4) PETROL CONSUMPTION TESTS. (5)… | ||
| img003 | The fundamental points for judging car performance. | ||
| View original record | REF. Hs/Rm2/LG121025. FUNDAMENTALS OF CAR PERFORMANCE. We frequently have quoted performances of various cars, but owing to incomplete information, the figures are of little value. We therefore submit… | ||
| img004 | Explaining the relationship between car weight, engine power, and acceleration, illustrated with two graphs. | ||
| View original record | - 2 - REF. Hs/Rm2/LG121025. (1) ACCELERATION. (a) Direct drive - car weight. The acceleration of two cars which are otherwise exactly similar will be inversely proportional to their weights throughout… | ||
| img005 | Page discussing tractive resistance, carburation, and flywheel inertia in relation to car performance and acceleration. | ||
| View original record | - 3 - REF. Hs/Rm2/LG121025. The same argument applies to axle ratio alterations as more power is then available at the same speed up to the peak of the power curve. The shape of the torque curve of… | ||
| img006 | Engine torque curves and their effect on vehicle acceleration, comparing two different performance profiles. | ||
| View original record | - 4 - REF. Hs/Rm2/LG121025. accelerating at 10 ft/sec², on bottom gear the flywheel was removed, the acceleration would increase automatically to 12 ft/sec², or 20%. Naturally, therefore a car noted… | ||
| img007 | Guide on comparing car efficiency by calculating displacement per ton mile and considering tractive resistance. | ||
| View original record | - 5 - REF. Hs/Rm2/LG121025. of the car engine is a compromise according as to whether a town carriage or sports car is required. Before comparing two cars for efficiency it is as well to ascertain:-… | ||
| img008 | The effects of wind resistance and streamlining on car performance, leading into a section on hill climbing. | ||
| View original record | - 6 - REF. Hs/Rm2/LG121025. is very high. For all normal comparative tests, however, we should say that these factors can be disregarded. Wind resistance. As this increases as the square of the speed,… | ||
| img009 | Vehicle hill climbing performance versus acceleration capabilities, with specific reference to the Phantom model. | ||
| View original record | - 7 - REF. Hs/Rm2/LG121025. output is required from them as in hill climbing, than when full power and increasing engine speed is required from them as in acceleration. For practical purposes,… | ||
| img010 | Graph and text explaining the relationship between acceleration and surmountable gradients for hill climbing. | ||
| View original record | - 8 - REF. Hs/Rm2/LG121025. ACCELERATION EQUIVALENT OF HILL CLIMBING. Surmountable gradients. Torque curve, car weight, displacement. As hill climbing is so closely related to acceleration, it is… | ||
| img011 | Page discussing high-speed performance, covering windage, exhausts, and streamlining, with an accompanying performance graph. | ||
| View original record | - 9 - REF. Hs/Rm2/LG121025. Graph Labels: Vertical Axis: ROAD WHEEL H.P Horizontal Axis: ROAD SPEED M.P.H. A B = Loss in max. speed due to under-gearing (1.5 m.p.h.) C D = Loss in max. speed due to… | ||
| img012 | The effects of streamlining and gear ratios on car performance, referencing the Thomas Special car. | ||
| View original record | - 10 - REF. Hs/Rm2/LG121025. streamlining. This was actually accomplished on The Thomas Special car this year. It is not generally realised that the outline of a car beneath the frame is of great… | ||
| img013 | Explaining the effect of wind on the maximum speeds of touring cars. | ||
| View original record | Hs/Rm/LG15.2.26. FUNDAMENTALS OF CAR PERFORMANCE. Effect of wind on the maximum speeds of touring cars. The maximum speeds on the level in still air of the two R-R touring models are 61 and 72 m.p.h.… | ||
| img014 | Graph and analysis showing the effect of wind on a car's maximum speed and the required horsepower. | ||
| View original record | - 2 - acceleration and consequently the power available is already falling off at the 'still air' maximum speed. GRAPH I. EFFECT OF WIND ON CAR MAXIMUM SPEED TABLE FROM GRAPH: H.P. TO DRIVE CAR AT… | ||
| img015 | With a graph showing the horsepower required to overcome wind resistance at various road speeds. | ||
| View original record | - 3 - Hs/Rm/LG15.2.26. If on the other hand the car is originally travelling at 60 m.p.h. and a head wind of 10 m.p.h. again blows upon it, the extra H.P. necessary to keep the car going is 20 HP. In… | ||
| img016 | Index outlining the fundamentals of car performance with a focus on the cooling system. | ||
| View original record | FUNDAMENTALS OF CAR PERFORMANCE. THE COOLING SYSTEM. (1) GENERAL PRINCIPLES INVOLVED. a Heat generating characteristic of the power unit. b Heat dissipating capacity of the cooling system. (2) FACTORS… | ||
| img017 | Explaining the general principles of heat generation and loss in a petrol engine, using the Silver Ghost as an example. | ||
| View original record | (1) GENERAL PRINCIPLES INVOLVED. (a) Heat generating capacity of power unit. An automobile petrol engine is a machine for converting heat units as supplied by the petrol into useful work. However… | ||
| img018 | Technical explanation of the fundamental methods of heat dissipation in a cooling system, focusing on conduction and convection. | ||
| View original record | - 2 - That is, in this case, almost one-third of the total heat contained in the petrol is rejected to the cooling system. (b) Heat dissipating capacity of the cooling system. There are three… | ||
| img019 | Engine cooling systems, heat dissipation, and heat generation factors in petrol engines. | ||
| View original record | - 3 - the liquid surrounds the cylinders, the waste engine heat evaporates it, it is then condensed by passing through some form of radiator and is returned to the cylinder. It should be noted that in… | ||
| img020 | Page discussing factors affecting engine cooling, including the influence of combustion chamber design. | ||
| View original record | - 4 - full throttle conditions only. While the heat dissipating capacity of a radiator can be predicted with very fair accuracy, the heat imparted to a cooling system by the power unit varies widely… | ||
| img021 | Comparison of engine heat rejection and efficiency between Silver Ghost, Phantom, and Hispano engines via two graphs. | ||
| View original record | - 5 - less B.HP. than the others, gives 20% more heat to the cooling water than either of them. The Hispano gains somewhat from com-pression ratio but the graph is sufficient to shew what diverse… | ||
| img022 | Page discussing engine compression ratios and their effect on heat transfer to the cooling system, including a graph of test results. | ||
| View original record | - 6 - (c) Compression ratio. As long as detonation is not incurred thereby, raising the compression ratio of an engine reduces the amount of heat given to the cooling water because the benefit… | ||
| img023 | Page discussing engine dimensions, thermal losses, and radiator size, including a comparative graph. | ||
| View original record | - 7 - goes up as the cube of the dimensions, while the area of the walls exposed to the burning charge only increases as the square of the dimensions. Again, a long stroke engine gains over a short… | ||
| img024 | The influence of fuel mixture strength on engine cooling, featuring a graph specific to a Silver Ghost engine. | ||
| View original record | - 8 - (e) Influence of mixture strength. Mixture strength has a marked effect on the quantity of heat imparted to the cooling water. An exceptional case is that of the Hispano where by running with… | ||
| img025 | Engine carbonisation, aluminium pistons, and conventional water cooling systems. | ||
| View original record | - 9 - (g) Carbonisation. A dirty engine will not cause a car to over-heat unless it promotes detonation which is only likely to occur where a fairly high compression is used. (h) Aluminium pistons.… | ||
| img026 | Technical analysis of how increasing water flow through the radiator core affects engine overheating and critical atmospheric temperature. | ||
| View original record | - 10 - (2) A rapid flow of water through the radiator core increases (a) The amount of heat the core can dissipate when the car is on the point of over-heating. (b) The critical atmospheric… | ||
| img027 | Page from a report on radiator efficiency, comparing the effects of rapid versus sluggish water circulation on heat dissipation. | ||
| View original record | - 11 - Again, suppose the car with the rapid circulation could be made to boil with an atmospheric temperature of 10°C. The difference in temperature between the radiator and atmosphere at this point… | ||
| img028 | Graph of radiator efficiency versus water flow, with a comparison of thermosyphon and pump circulation cooling systems. | ||
| View original record | - 12 - GRAPH VI Y-Axis: HEAT DISSIPATION PER CENT. X-Axis: WATER FLOW THROUGH RADIATOR CORE GAL/MIN The curve is taken from one of the American Bureau of Standard's papers. The full data of the test… | ||
| img029 | Page discussing thermosyphon cooling systems and types of radiator cores. | ||
| View original record | - 13 - WATER INCREASING IN DENSITY AS IT COOLS. By employing water connections to the radiator of ultra generous dimensions, and arranging the top of the radiator to be the maximum height above the… | ||
| img030 | Comparison of the efficiency of various radiator core designs, including diagrams and analysis. | ||
| View original record | - 14 - DIAGRAM TEXT: DISC FINS. STRIP FIN. CONTINUOUS FIN. EXAMPLES OF FIN & TUBE CORES. STRAIGHT RIBBON SQUARE CELL. 50% DIRECT. ZIG ZAG RIBBON HEXAGONAL CELL. 40% DIRECT. ZIG ZAG RIBBON DIAGONAL… | ||
| img031 | Page discussing radiator core efficiency and the limiting efficient depth of the core, with a comparative chart. | ||
| View original record | - 15 - [Chart Data] LEFT COLUMN (AIR VEL. THROUGH CORE 25 FT/SEC): B: 72% C: 53% A: 50% RIGHT COLUMN (AIR VEL. THROUGH CORE 50 FT/SEC): B: 100% * C: 91% A: 68% CHART TITLE: TYPES OF RADIATOR CORE… | ||
| img032 | The value of bonnet ventilation for radiator cooling efficiency, with test data from a Silver Ghost. | ||
| View original record | - 16 - (d) Ventilation value. It is clear that as the cooling capacity of a radiator depends upon the air velocity through the core, it is essential for maximum efficiency that once air has passed… | ||
| img033 | Page discussing engine cooling challenges in large cars and the possibilities and limitations of cooling fans. | ||
| View original record | - 17 - (e) Handicap of large car As we have previously shewn, a large engine gives less heat to the cooling water per B.HP. generated than a small engine of similar design. It may therefore be a… | ||
| img034 | Comparison of engine cooling fan performance, including a graph plotting thrust versus engine RPM for different fan models. | ||
| View original record | - 18 - fan increases approximately as the cube of the r.p.m. This means that in order that a fan may produce a considerable flow of air through the radiator at low speeds, an immense strain must be… | ||
| img035 | Comparison of relative strains on fan belts for different engine models, including a graph. | ||
| View original record | - 19 - the Phantom fan belt having to transmit almost twice the power of that of the Hispano, the Silver Ghost more than three times. It is quite clear that no normal fan belt can be expected to… | ||
| img036 | Page discussing engine fan design variations, including a performance comparison graph between two fan types. | ||
| View original record | - 20 - cars to drive the fan through a small friction drive directly off the front end of the camshaft. The friction drive is evidently supplied to prevent the fan absorbing an unnecessary amount of… | ||
| img037 | The principles of water cooling under pressure, including a graph showing boiling point versus gauge pressure for a Silver Ghost radiator. | ||
| View original record | - 21 - (5) WATER COOLING UNDER PRESSURE. (i) Principles. Under normal atmospheric pressure of 14.7 lbs/sq.in. water boils at 100°C. If this pressure is reduced by creating a partial vacuum, the water… | ||
| img038 | The method of pressurizing the water cooling system and its effect on efficiency, mentioning the R-R Silver Ghost. | ||
| View original record | - 22 - atmospheric temperature was 25°C, by raising the boiling point from 100°C to 110°C, this critical atmospheric temperature would be increased to 35°C, or from quite a normal atmospheric… | ||
| img039 | The disadvantages of a cooling system and the principles of evaporative cooling. | ||
| View original record | - 23 - "Increasing the efficiency of the system" is rather a bad expression to use in this connection because actually its cooling efficiency remains unchanged. What is actually done is to "decrease… | ||
| img040 | Description of a steam-based engine cooling system using a gear pump, including an illustrative diagram. | ||
| View original record | - 24 - pump in place of the centrifugal type. The principle is this:- Boiling water is circulated round the engine cylinders and naturally in the process steam is generated. The steam is led into the… | ||
| img041 | Page from a report discussing the efficiency gain from using an evaporative engine cooling system. | ||
| View original record | - 25 - longer deal with all the steam generated, a relief valve allows steam to escape from the top of the radiator. (ii) Maximum gain in efficiency. Evaporative cooling cannot be looked upon as a… | ||
| img042 | List of the advantages and disadvantages of evaporative cooling systems. | ||
| View original record | - 26 - (iii) Advantages and disadvantages. The advantages of evaporative cooling are:- (a) Increase of 6½% in efficiency. (b) Automatic temperature control. The temperature of the system is always… | ||
| img043 | Various engine cooling methods, including liquid and air cooling. | ||
| View original record | - 27 - It will be observed that the last four difficulties are susceptible to partial or total elimination by design. The first presents a more obstruse problem. The chief difference between… | ||
| img044 | Methods for comparing the relative efficiency of car cooling systems. | ||
| View original record | - 28 - to be made by the fan, partially owing to the large expansions which take place owing to the wide range of working temperature of the cylinders making such things as small tappet clearances… | ||
| img045 | Procedure for testing and comparing vehicle radiator performance during a hill climb. | ||
| View original record | - 29 - hill preferably not less than three miles long - insert through a hole in the radiator cap (or a cork replacing this) one glass thermometer in the top tank of each radiator. Take the… | ||
| img046 | Page outlining procedures for testing cars, including towing for hill climbing simulation and considerations for investigating cooling systems. | ||
| View original record | - 30 - be selected and a second car attached to the one to be tested by means of a tow rope. If this car is then towed in top or 3rd gear at a fixed speed it will give hill climbing conditions. Care… | ||
| img047 | The method employed for petrol consumption tests on a New Phantom model. | ||
| View original record | EXPERIMENTAL REPORT EXPL No REF. Hs/Rm1/LG21. 11. 25. NEW PHANTOM - PETROL CONSUMPTION TESTS. METHOD EMPLOYED. These tests were carried out on an open touring car weighing 2,516 tons, fitted with… | ||
| img048 | The methodology and results of fuel consumption tests. | ||
| View original record | - 2 - EXPERIMENTAL REPORT. EXPL. No. REF. Hs/Rm1/LG21.11.25. These two readings gave accurately the rate of fuel consumption and the average road speed during the test, the latter being quite… | ||
| img049 | Page discussing factors that affect petrol consumption, such as engine friction, speed, and carburetter settings. | ||
| View original record | - 3 - EXPERIMENTAL REPORT. EXPL. No. REF. Hs/Rm1/LG21.11.25. It will be observed what a large part engine friction and pumping losses play in increasing petrol consumption at slow speeds. As the… | ||
| img050 | The fuel economy possibilities of the Phantom model. | ||
| View original record | EXPERIMENTAL REPORT. EXPL. No. REF. Hs/Rm/LG21.11.25. - 4 - FUEL ECONOMY POSSIBILITIES - PHANTOM. The figures given on this blue print (No. 4) may seem somewhat contradictory. It is obvious that if an… | ||
| img051 | Blueprint diagram for a flow meter to measure petrol consumption. | ||
| View original record | FLOW METRE FOR MEASURING PETROL CONSUMPTIONS. A. TWO WAY TAP B. FUEL TANK. C. THREE WAY TAP X. 500cc. PIPETTE Y. 120cc. PIPETTE B. Y 120 CC'S. 500cc. X. A C To CARB. WHEN TAP 'A' IS TURNED ON, THE… | ||
| img052 | Car performance, focusing on petrol consumption and optimum driving speed. | ||
| View original record | - 5 - EXPERIMENTAL REPORT. EXPL. No. REF. Hs/Rm/LG21.11.25. to be done, the thermal losses will be very substantially increased per I.H.P. produced. CAR PERFORMANCE. PETROL CONSUMPTION. There is… | ||
| img053 | Page illustrating the thermal efficiency curve of a 4-stroke petrol engine and discussing the performance of the Phantom model. | ||
| View original record | - 6 - EXPERIMENTAL REPORT. EXPL. No. REF. Hs/Rm1/LG21.11.25. The graph below illustrates this:- GRAPH 1. GRAPH I THERMAL EFFICIENCY 4%, 8%, 12%, 16%, 20%, 24% PERCENTAGE FULL LOAD ON ENGINE 0, 20%,… | ||
| img054 | Gear ratios and their effect on car economy and road speed. | ||
| View original record | - 7 - EXPERIMENTAL REPORT. EXPL. No. REF. Hs/Rm/LG21.11.25. GEAR RATIO. It is for this reason that a high gear ratio reduces the petrol consumption; though the actual work required to drive the car is… | ||
| img055 | The effects of acceleration and four-wheel brakes on petrol consumption. | ||
| View original record | - 8 - EXPERIMENTAL REPORT. EXPL. No. REF. Hs/Rm/LG21.11.25. 17½ m.p.h. If the speed is pushed up to 50 m.p.h. the petrol consumption will be doubled. ACCELERATION. Acceleration is bad for petrol… | ||
| img056 | Carburation and petrol consumption, illustrated with a graph of typical curves for a 4-stroke petrol engine. | ||
| View original record | - 9 - EXPERIMENTAL REPORT. EXPL. No. REF. Hs/Rm/LG21.11.25. when these are fitted, instead of making a gradual stop with the throttle closed. Again, the average speed of the car almost always is… | ||
| img057 | Carburettor settings and ignition advance, with a graph showing brake load versus spark advance. | ||
| View original record | - 10 - EXPERIMENTAL REPORT. EXPL. No. REF. Hs/Rm/LG21.11.25. thermal efficiency dropping from 17% to 11% with no appreciable loss in power. As for accelerating and starting from cold, an over-rich… | ||
| img058 | Engine friction, rolling resistance, and factors affecting fuel consumption. | ||
| View original record | - 11 - EXPERIMENTAL REPORT. EXPL. NO. REF. Hs/Rm1/LG21.11.25. at very small throttle openings some 20° extra advance can be given with beneficial results, the car could never be run under these… | ||
| img059 | Two graphs showing the effects of speed, tyre pressure, and mixture control on petrol consumption. | ||
| View original record | TOP GRAPH: EFFECT OF SPEED & TYRE PRESSURE ON PET. CONSUMPTION. WATER TEMP. 80°C. IGNITION STANDARD MIXTURE CONTROL CENTRAL AXLE 15 x 52 TYRES STANDARD Graph Title: TYRE INFLATION PRESSURE Y-Axis:… | ||
| img060 | Series of graphs showing the effect of ignition advance, axle ratio, and engine temperature on petrol consumption. | ||
| View original record | EFFECT OF IGNITION ADVANCE ON PETROL CONSUMPTION. WATER TEMP. 80°C. AXLE 15 x 52 SPEED 30 M.P.H. TYRE PRESS 50 LBS/SQ." MIXTURE CONTROL CENTRAL TYRES. STANDARD. Graph 1: Title: IGNITION ADVANCE.… | ||
| img061 | Theoretical and actual fuel economy improvements in M.P.G. for the Phantom model. | ||
| View original record | FUEL ECONOMY POSSIBILITIES PHANTOM THEORETICAL IDEAL FACTOR TO BE ELIMINATED. MAX. POSSIBLE IMPROVEMENT IN M.P.G. A. ROLLING & WIND RESISTANCE, TYRE POWER TRANSMISSION LOSSES. 35% B. ENGINE FRICTION &… | ||
| img062 | The action, adjustment, and limitations of the New Phantom carburetter. | ||
| View original record | EXPERIMENTAL REPORT. EXPL. No. REF. Hs/ACL/LG261125. A BRIEF DESCRIPTION OF THE ACTION, ADJUSTMENT AND LIMITATIONS OF THE NEW PHANTOM CARB. WITH METHOD OF RECTIFYING TROUBLES POSSIBLE TO ENCOUNTER.… | ||
| img063 | Formula for the velocity of petrol flow. | ||
| View original record | EXPERIMENTAL REPORT. EXPL. No. REF. Hs/ACL/LG261125. amount needed. The following example will illustrate the point. The velocity of petrol flow (v) may be expressed by the following formula:- v^2 =… | ||
| img064 | Carburetter performance, focusing on air/petrol velocity and mixture richness in the New Phantom model. | ||
| View original record | EXPERIMENTAL REPORT. EXPL. No. REF. Hs/ACL/LG261125 - 3 - than at high speeds. We see that an increase of air velocity from 40 ft/sec. to 80 ft/sec. results in an increase in petrol velocity from .387… | ||
| img065 | Carburettor adjustments and conditions for a New Phantom carburetter. | ||
| View original record | - 4 - EXPERIMENTAL REPORT. EXPL. No. REF. Hs/ACL/LG261125. the following conditions should be satisfied by the adjustment, assuming of course that the carb. is built up correctly. (1) That the low… | ||
| img066 | With two graphs showing carburettor mixture control adjustments under different conditions. | ||
| View original record | - 5 - EXPERIMENTAL REPORT. EXPL. No. REF. Hs/ACL/LG261125. First Graph: POSITION OF CONTROL REQUIRED TO GIVE CORRECT MIXTURE WHEN JET SET TOO EARLY. Y-Axis: POSITION OF MIXTURE CONTROL, NOTCHES WEAK,… | ||
| img067 | Possible troubles caused by incorrect carburetter settings and the automatic range. | ||
| View original record | - 6 - EXPERIMENTAL REPORT. EXPL. No. REF. Hs/ACL/LG261125. POSSIBLE TROUBLES CAUSED BY INCORRECT SETTING. It is quite possible for trouble to occur through the incorrect setting of the low speed jet… | ||
| img068 | Carburettor adjustments, function at low speeds, and prerequisites for tuning. | ||
| View original record | - 7 - EXPERIMENTAL REPORT. EXPL. No. REF. Hs/ACL/LG261125. At a speed below that at which the air valve starts to lift the carburetter is not automatic and the mixture will become rapidly weaker as… | ||
| img069 | Petrol grades, fuel supply, and carburettor adjustments. | ||
| View original record | - 8 - EXPERIMENTAL REPORT. EXPL. No. REF. Hs/ACL/LG261125. grade of petrol or a cold hot-spot - could give rise to symptoms which might be mistaken for faulty metering of the carburetter and although… | ||
| img070 | The procedure for setting the low speed jet of a carburetter. | ||
| View original record | - 9 - EXPERIMENTAL REPORT. EXPL. No. REF. Hs/ACL/LG261125. normal working temperature and the jacket water at approx. 80° C. SETTING LOW SPEED JET. With regard to the adjustment of the low speed jet… | ||
| img071 | Carburettor mixture testing, troubleshooting, and performance comparison between Phantom and Silver Ghost models. | ||
| View original record | - 10 - EXPERIMENTAL REPORT. EXPL. No. REF. Hs/ACL/LG261125. found by experiment, will probably vary slightly from the above figure but no excessive variation should occur as this should indicate some… | ||
| img072 | Troubleshooting guide listing engine running problems and their probable causes. | ||
| View original record | - 11 - EXPERIMENTAL REPORT. EXPL. No. REF. Hs/ACL/LG261125. TROUBLE. PROBABLE CAUSE. Richness at low speeds light loads. 1: Jet set before air valve starts to lift. 2: Diaphragm set too low down in… | ||
| img073 | Page discussing the fundamental laws of vehicle braking, focusing on road surface friction and retardation. | ||
| View original record | - 11 - REF. Hs/Rm2/LG121025 (5) B R A K I N G . Fundamental laws. Weight of car. Gradients. Distance, and time to rest. Windage. Rotating parts, and pedal pressure. Max. rate of retardation. Personal… | ||
| img074 | The effects of vehicle weight and gradients on braking performance and stopping distances. | ||
| View original record | - 12 - REF. Hs/Rm2/LG121025. Weight of the car. If all the wheels of the car are locked the distance in which it will stop is entirely independent of the weight of the car. With the R-R front wheel… | ||
| img075 | Analysing vehicle stopping distances and times, including a graph. | ||
| View original record | - 13 - REF. Hs/Rm2/LG121025. in which a car can be brought to rest varies directly as the square of the speed at which the car is travelling. If therefore a car's best stop from 20 m.p.h. is 20 ft.,… | ||
| img076 | Pedal pressure required to lock wheels at high speeds and the limits of vehicle retardation for passenger comfort. | ||
| View original record | - 14 - REF. Hs/Rm2/LG121025. Pedal pressure. The increase in pedal pressure require to lock the wheels at high speeds is largely due to the energy of the rotating parts. Even if the wheels are not… | ||
| img077 | Blueprint containing two graphs showing practical braking figures obtained with a three-pen chronograph. | ||
| View original record | PRACTICAL BRAKING FIGURES OBTAINED WITH THREE PEN CHRONOGRAPH. Graph A: Y-Axis: ROAD SPEED M.P.H. X-Axis: DISTANCE TO REST. FEET. Boxed Text: OPEN TOURING CAR BRAKING. DISTANCE TO REST. 40% BRAKING ON… | ||
| img078 | Two graphs illustrating the effect of brake distribution and road surface variation on vehicle stopping distance. | ||
| View original record | TOP GRAPH: ROAD SPEED M.P.H. CURVE 'A' CURVE 'B' CURVE 'C' EFFECT OF BRAKE DISTRIBUTION. OPEN TOURING CAR. WHEELBASE LENGTH 150" HT. OF C. OF G. 26" COEFF. OF FRN. BETWEEN TYRE & ROAD .7 WTS. FRONT… | ||
| img079 | Description of the four-wheel braking system and its servo mechanism. | ||
| View original record | DESCRIPTION OF THE R.R. SYSTEM OF FOUR WHEEL BRAKES. In the RR. system, all the four wheels are braked by application of the foot pedal. The hand brake operates only on the rear wheels and is exactly… | ||
| img080 | Description of an improved semi-servo four-wheel braking system, detailing its operation and the function of the servo components. | ||
| View original record | - 2 - various levers - to the rear brakes in a very similar manner to the method employed on the RR. cars with the rear brake only. This braking system is an improved semi-servo system. It is seen… | ||
| img081 | The operation and adjustment of a servo-assisted braking system with equalisers. | ||
| View original record | - 3 - the end of the equaliser lever D. and exert a pull in the brake ropes. The two levers A. and B. are inserted between the rod from the pedal to the rear equaliser. This is the direct pull to the… | ||
| img082 | Instructions for setting up and adjusting the four-wheel brake system. | ||
| View original record | INSTRUCTIONS FOR SETTING UP AND ADJUSTING THE RR. FOUR WHEEL BRAKE SYSTEM. It is most essential in the setting up and adjusting of the RR. four wheel brake system that the following instructions are… | ||
| img083 | Instructions for brake adjustment, including serrated adjustment, toggle settings, and bedding. | ||
| View original record | - 2 - Serrated adjustment. Place this in the first notch position so that the actuating lever is in its lowest position in relation to the cam. There should be 5 notches remaining to adjust for wear.… | ||
| img084 | Instructions for checking and adjusting brake pull levers, rods, and ropes. | ||
| View original record | - 3 - cams should not be used as stops. As a further check, if the pull rod is disconnected the cam operating lever should move upwards about .4" measured at its end - see drawing. When the brake… | ||
| img085 | Technical instructions for setting up rear brakes and servo systems on a 40/50 RR car. | ||
| View original record | - 4 - case it will tend to raise these levers off their stops. If they are raised off their stops the amount must not exceed 1/32" and the free movement at the end of the cam operating lever must not… | ||
| img086 | Technical description of a servo mechanism's operation, adjustment, and maintenance. | ||
| View original record | - 5 - The 3 pins (G. 72459) are to prevent the two plates rotating independently of each other. These pins should work perfectly freely and accurately in the bushes because they have to transmit half… | ||
| img087 | Instructions for adjusting brake system components, including serrated adjustments, levers, and pedal movement. | ||
| View original record | - 6 - obtained, will hold it in that position. Another function of this serrated adjustment is that with careful use it should be impossible to adjust the plates so that there is no clearance and they… | ||
| img088 | Instructions for the adjustment of the four-wheel braking system. | ||
| View original record | Hs4/LGS.7.24. ADJUSTMENT OF THE RR. FOUR WHEEL BRAKING SYSTEM. The places for adjustment of the system are:- (1) REAR BRAKES. The serrated adjustment on the cam operating levers. (2) FRONT BRAKES. The… | ||
| img089 | Instructions for checking and adjusting the front brakes, including clearances and operating mechanism movements. | ||
| View original record | - 2 - Hs4/LGS.7.24. It should be borne in mind that correct pedal travel is in no way an indication that the front brakes are correctly set because these are entirely servo operated and will not… | ||
| img090 | Instructions for checking front brake clearances and adjusting the servo. | ||
| View original record | - 3 - Hs4/LGS.7.24. In this event it is possible for one lever to be on the stop and the other will then be twice its normal distance off the stop. This would give rise to error in checking the… | ||
| img091 | Instructions for checking and adjusting brake system clearances and pedal return. | ||
| View original record | - 4 - Hs4/LG8.7.24. by the serrations. Care should be taken to see that these serrations are properly in mesh after adjustment has been made and before the clearance is checked. Another check for the… | ||
| img092 | The variations of the four-wheel braking system, including brake force distribution and the effects of maximum braking on steering. | ||
| View original record | Hs2/LGS.7.24. POSSIBLE VARIATIONS OF THE RR. FOURWHEEL BRAKING SYSTEM. As stated previously, the leverage is so proportioned that of the total braking effort - 40% goes to the front brakes while the… | ||
| img093 | Technical explanation of the semi-servo braking system's characteristics and effects on vehicle handling. | ||
| View original record | - 2 - Hs2/LG8.7.24. It is for this reason drivers should be impressed that they should make a habit of releasing the brakes when actually turning a corner. Very efficient front brakes also increase… | ||
| img094 | Page from a document explaining brake servo operation, fault diagnosis, and pedal pressure variation. | ||
| View original record | - 3 - Hs2/LGS.7.24. brake ropes, this is maintained until the brakes are released, although the servo is not going round. If there is any noticeable variation as regards equali- sation, or the amount… | ||
| img095 | Guide on diagnosing steering pull from unequal braking and the philosophy of front brake setup. | ||
| View original record | - 6 - brakes only, that this occurs and as we are still using the same brakes, there is no reason for this to be different. If there is a tendency for the steering to pull to the right, it will be due… | ||
| img096 | Procedure for testing servo efficiency using an apparatus with two spring balances. | ||
| View original record | TESTING THE SERVO EFFICIENCY. Apparatus for testing the efficiency of the servo can easily be fitted up to work either on the car or on the Gearbox testing rig. It is probably preferable to do the… | ||
| img097 | Instructions and considerations for testing a brake servo system, including notes on pedal pressure and friction lining temperature. | ||
| View original record | - 2 - Hsl/LG9.7.24. The following points should be noted when carrying out tests:- Do not apply sufficient effort to the pedal to lock the rear wheels as this stops the servo rotating and if any… | ||
| img098 | Diagram and procedure for testing servo efficiency using spring balances. | ||
| View original record | APPARATUS FOR TESTING SERVO EFFICIENCY. SPG. BAL. A SPG. BAL. B "STEP ASIDE" COUNTERSHAFT. TO FRONT THE ABOVE DIAGRAM SHOWS THE METHOD OF INSERTING THE MAXIMUM READING SPRING BALANCES IN THE LINKAGE… | ||
| img099 | Graph showing braking units and percentage of braking on front wheels for varying servo torque multiplication. | ||
| View original record | CURVES GIVING THE DIFFERENT BRAKING & THE PERCENTAGE OF BRAKING ON FRONT WHEELS FOR VARYING SERVO TORQUE MULTIPLICATION. THE BRAKING UNITS GIVEN ARE ASSUMING UNIT PEDAL PRESSURE & TAKEN AS THE LOAD IN… | ||
| img100 | Index page outlining topics related to car steering performance and fundamentals. | ||
| View original record | FUNDAMENTALS OF CAR PERFORMANCE. S T E E R I N G. I: REQUIREMENTS AND LIMITATIONS OF MODERN CAR STEERING. a Desirable attributes. b Limiting factors. c Reversible and non-reversible steerings. II:… | ||
| img101 | The requirements and limitations of modern steering gear, including desirable attributes and limiting factors. | ||
| View original record | FUNDAMENTALS OF CAR PERFORMANCE. (1) REQUIREMENTS AND LIMITATIONS OF MODERN STEERING GEAR. (a) Desirable attributes. The main features required in a modern steering gear are - Lightness of operation,… | ||
| img102 | Steering gear design, addressing road shocks, steering effort, and high-speed wobbles in large vehicles. | ||
| View original record | - 3 - be increased and the drivers hands move through a larger distance for unit angular displacement of the road wheels. It is obvious that there is a limit to the number of complete rotations of the… | ||
| img103 | Graph and explanation concerning the effort required to steer a car and the types of steering gear. | ||
| View original record | - 4 - GRAPH I EFFORT REQUIRED TO STEER CAR. Y-AXIS: LBS/INS TORQUE AT PIVOT PIN TO MOVE WHEELS X-AXIS: TYRE PRESSURES LBS/D" DATA SERIES 1: HISPANO V 40/50 DATA SERIES 2: 40/50 FRONT AXLE WEIGHTS 2695… | ||
| img104 | Technical discussion on reversible and semi-reversible steering systems and their efficiency. | ||
| View original record | - 5 - reversibility of this type of steering depends entirely on the helix angle of the teeth. (1) Reversible. The simplest example of a reversible steering is that of the bevel and crown wheel type.… | ||
| img105 | Page discussing irreversible steering systems, including a graph on screw and nut efficiency. | ||
| View original record | - 6 - nut becomes self-locking with a helix angle of 6°. This clearly demonstrates the difficulty of protecting a driver from road shocks and at the same time giving him finger-light steering on a… | ||
| img106 | Various types of steering gear mechanisms with illustrations. | ||
| View original record | - 7 - (II) TYPES OF STEERING GEAR. (a) Completely reversible. Bevel pinion and sector - takes up a lot of room. Spur pinion and rack. Planetary system. RACK & PINION. SIZAIRE. EPICYCLIC SINGER. (b)… | ||
| img107 | Page comparing Ross and Marles steering mechanisms and defining the fundamentals of centre-point steering layout. | ||
| View original record | - 8 - such as the "Ross". These enable a greater leverage to be obtained on a lock than when running straight. Chief disadvantage - small area of wearing surface, lack of strength due to design… | ||
| img108 | Technical note on centre-point steering and the effects of transversally raked pivots. | ||
| View original record | - 9 - the pivot. This means in other words, when one front brake only is applied, the steering can remain unaffected. As pointed out under the sub-section on Braking, however, centre-point steering… | ||
| img109 | The design and effects of different steering pivot geometries, including transverse and longitudinal rake. | ||
| View original record | - 10 - The maximum transverse rake adopted in practice is about 8°. SKETCH A. TRANSVERSALLY RAKED PIVOTS. Y. DISTANCE THROUGH WHICH PIVOT IS RAISED WHEN ROADWHEEL TURNS THROUGH 90° (c) Vertical… | ||
| img110 | Page discussing the self-centering characteristics of steering systems, with diagrams illustrating pivot types and force moments. | ||
| View original record | - 11 - SKETCH B. VERTICAL PIVOT. LONGITUDINALLY RAKED PIVOTS. (e) Self-Centering. We have already pointed out two features on a conventional steering system which tend to promote self-centering. Of… | ||
| img111 | Page discussing the principles of wheel camber and wheel-gather (toe-in), with an illustrative blueprint. | ||
| View original record | - 12 - would still have a tendency to self-centre due to the different inclinations of the stub axle on a lock. This is illustrated in sketch C. (f) Wheel camber. As we have previously shewn, in order… | ||
| img112 | Page discussing the theory of toe-in and wheel gather for cambered wheels to achieve optimal tyre wear. | ||
| View original record | - 13 - [Text from top diagram] Y X - Y = 1/4" TO 3/8" X A theory is also propounded that with 'cambered' wheels toe-in is necessary to produce the best tyre wearing results, the idea being that the… | ||
| img113 | Analysis of heavy left-hand steering, including a table of load measurements and a graph illustrating leverage differences. | ||
| View original record | - 14 - high speed steering wobbles in some cars. In these cases this is the limiting factor in the amount of 'gather' which can be employed. (h) Heavy left-hand steering. It is not generally realised… | ||
| img114 | The nature of high speed wheel wobble or wheel tramping, including diagrams. | ||
| View original record | - 15 - In other words, the left-hand lock requires about 33% more effort than the right-hand lock. A consideration of Graph III will shew why this is, the leverage available falling off considerably… | ||
| img115 | Analysis of front axle wobble (shimmy), its relationship with wheel revolution speed, and the design challenges presented by modern components. | ||
| View original record | - 16 - Every front axle when it oscillates in a criss-cross manner wants to do so at a fixed rate. The number of criss-cross vibra- tions or wobbles it wishes to make per minute varies with the… | ||
| img116 | Technical analysis of high speed wheel wobble, its sustaining factors, and causes. | ||
| View original record | - 17 - That is, the lower the wobble frequency, the greater the amplitude of wheel flap. If at 40 m.p.h. the wheels turn through 14°, when a wobble occurs at 60 m.p.h. they may only turn through 8°.… | ||
| img117 | Analysis of vehicle wobbles, focusing on the effects of balloon tyres and wheel imbalance. | ||
| View original record | - 18 - We have proved this by fastening heavy lead bands round the front brake drums, wobbles then came on at a lower speed and were more violent than before. Similarly without front wheel brakes the… | ||
| img118 | The causes of wheel wobble and basic alterations to prevent its occurrence. | ||
| View original record | - 19 - force in the wheel is exactly what is required to set it going. Again, in the manufacture of tyres, unavoidable errors occur so that even if the wheel is balanced, one portion of the tread… | ||
| img119 | Page discussing the causes of and preventative measures for front wheel wobble. | ||
| View original record | - 20 - 5. Independent front wheel suspension making the criss cross period of the frame very high. 6. Carrying the wheel contact out from centre-point as far as compatible with front wheel brake… | ||
| img120 | Page detailing steering adjustments and the causes and nature of low-speed wobbles. | ||
| View original record | - 21 - 8. Check wheel gather. Set wheels parallel. 9. Reduce castoring to the minimum to give self-centering. 10. Reduce the strength of the side steering tube springs to the minimum consistent with… | ||
| img121 | The causes and preventatives for low-speed steering wobbles, page 22. | ||
| View original record | - 22 - 2. Weak side steering tube springs. 3. Any side steering tube springs with non-reversible steering. 4. Centre point steering. 5. Large section, low inflation pressure tyres. 6. Good non-skid… | ||
| img122 | Precautions against low-speed wobbles and the effects of braking on steering. | ||
| View original record | - 23 - (3) Ascertain that the tyre inflation pressures are the maximum for the required riding comfort. These precautions should be sufficient to cure any R-R car of low speed wobbles. In exceptional… | ||
| img123 | Explanation of front axle control and the effects of braking torque on steering. | ||
| View original record | - 24 - one pair of wheels get on to a piece of loose or moist road surface where their powers of adhesion are reduced. (b) Front axle control. As we pointed out under 'Centre-point steering', the… | ||
| img124 | Page discussing the forces, couple, and torque acting on a front spring and axle when a wheel is locked, illustrated with two diagrams. | ||
| View original record | - 25 - friction between the tyre and the road is acting at the tyre in the opposite direction to the car momentum. These two forces constitute a couple. It is clear that if the pivot was very weak it… | ||
| img125 | Analysis of steering instability, self-centering, and the effects of braking on front axle and spring dynamics. | ||
| View original record | - 26 - Even with a normal front spring the leaves are twisted into a position something like this. Now it is clear that when the axle is tilted forward the pivot is also tilted forward. We have… | ||
| img126 | Page detailing various designs of leaf spring suspension to resist torsion during braking. | ||
| View original record | - 27 - increases the resistance of the spring to torsion when the brakes are applied. This is the simplest expedient and is that adopted by R-R. Other methods incorporate some sort of torque arm or… | ||
| img127 | Technical discussion on the effects of steering at high speeds and road shocks caused by out-of-balance wheels. | ||
| View original record | - 28 - These various designs indicate that the danger we have mentioned is widely appreciated in the automobile world. A point in connection with this subject is that the effect of steering taking… | ||
| img128 | The effects of balloon tyres on high-speed steering wobbles and road shocks, with reference to the Silver Ghost. | ||
| View original record | - 29 - bound point in the tyre tread exerts a pull of 160 lbs. at 60 m.p.h. so that there is an alternating couple of more than 300 ins. lbs. trying to turn the wheel in and out. (b) Balloon tyres.… | ||
| img129 | The screw and nut type steering reduction gear and its reversibility. | ||
| View original record | - 30 - directions are limited in the first case by the requirements of front wheel brakes and in the second by low speed wobbles and selectiveness. VIII THE ROLLS-ROYCE STEERING. (a) Type of reduction… | ||
| img130 | Steering nut efficiency, self-centering, and gear ratios for the Silver Ghost and New Phantom models. | ||
| View original record | - 31 - (2) That the nut has the highest efficiency attainable when it leaves the works. If this is not so, no self-centering will be obtained with the standard wheel castor and the car cannot be… | ||
| img131 | Steering characteristics, comparing the New Phantom and Silver Ghost models, including self-centering and road shocks. | ||
| View original record | - 32 - lock and at the same time promotes increased reversibility. The reason a lower gear ratio is necessary on the New Phantom is because the weight on the front wheels of this car is more than 2… | ||
| img132 | Pivot inclination and wheel wobbles, with blueprint sketches comparing the Silver Ghost and Phantom models. | ||
| View original record | - 33 - X in the sketch) and most favourable pivot inclination. The [Blueprint Diagram Text] Left Side (Silver Ghost): 2° 30' 5° ℄ WHEEL VERTICAL ℄ PIVOT SILVER GHOST .554 Right Side (Phantom): 2° 30'… | ||
| img133 | Issues with the Phantom car's steering through hydraulic shock dampers, a lightened front axle, and weight reduction. | ||
| View original record | - 34 - maximum speed of the Phantom car tend to turn this phenomenon, which on most cars including our own 20 HP., is only an exceptional occurrence, into an acute problem. Nevertheless by means of… | ||
| img134 | Blueprint detailing the test rig and procedure for measuring the efficiency of a steering worm and nut. | ||
| View original record | INSTRUCTIONS AND TACKLE FOR MEASURING THE EFFICIENCY OF STEERING WORM & NUT. 720 LEAD 'P' LBS. FORCE AT 20' LEVERAGE 'W' LBS. LOAD ANGLE PLATE & STAY ADJUSTABLE TO ACCOMODATE THE DIFFERENT TYPES OF… | ||
| img135 | The new Phantom engine lubrication system and the fundamentals of overoiling. | ||
| View original record | Hs/ACL/T19.5.26. THE NEW PHANTOM ENGINE LUBRICATION SYSTEM AND THE FUNDAMENTALS OF OVEROILING ON THESE ENGINES. The complete analysis of engine lubrication is naturally rather involved and it is not… | ||
| img136 | Performance curve and analysis of an average Phantom oil pump's capacity. | ||
| View original record | - 2 - Should, however, the pump be worn, resulting in large clearance between the gears and the case, the delivery will naturally be less than a leakproof pump. The following curve shews the pumping… | ||
| img137 | Description of the engine's oil pressure control system and the function of a spring-controlled release valve. | ||
| View original record | - 3 - If no means were employed to control the pressure and the path for leakage round the bearings remained constant, the discharge would increase in proportion to the engine speed, but the pressure… | ||
| img138 | Graph of oil pressure against RPM and a description of the lubrication system using a lower pressure release valve. | ||
| View original record | - 4 - Hs/ACL/T19.5.26. CURVE TAKEN WITH LOWER PRESS SPG. THAN STD. IN RELEASE VALVE. Oil Pressure LBS/□" R.P.M. RELIEF VALVE STARTS TO OPERATE. The above curve illustrates this point. The release oil… | ||
| img139 | Page discussing oil leakage in bearings, with a graph showing calculated oil pressure versus RPM due to centrifugal force. | ||
| View original record | - 6 - Hs/ACL/T19.5.26. Leakage takes place at all these bearings, particularly so at the "big ends" where the normal oil pressure is augmented by the centrifugal force exerted on the oil in the… | ||
| img140 | Engine oil pressure, bearing clearances, viscosity, and lubrication systems. | ||
| View original record | - 7 - Hs/ACL/T19.5.26. greater influence of the two. Another reason why reducing the bearing clearances is more important than the main pressure is that even with no main pressure, if oil were fed to… | ||
| img141 | Issues with overoiling, cylinder lubrication, and piston rings in an engine. | ||
| View original record | - 8 - Hs/ACL/T19.5.26. with very low oil pressures and large clearances it is left open to chance that some parts will take the greater part of the oil while others tend to starve. CYLINDER… | ||
| img142 | Page describing the operation and design of piston rings, focusing on oil control and the 'L' section ring. | ||
| View original record | - 9 - the ring grooves and shall "bed" evenly on the top and bottom spaces. If the rings have large clearance in the grooves the downward motion of the piston presses the ring against the top of the… | ||
| img143 | Piston ring design, focusing on the wedge-shaped oil film, wear characteristics, and scraping efficiency. | ||
| View original record | - 10 - being uniform, but increasing from its upper edge to a maximum at the lower, results in a wedge shaped oil film between it and the cylinder wall. The ring therefore tends to ride over the oil… | ||
| img144 | Experiments to reduce engine over-oiling, focusing on piston types and oil flow through bearings. | ||
| View original record | - 11 - Hs/ACL/T19.5.26. some of our experiments have shewn, but with any of the types tested we have been unable to effect a cure on a badly overoiling engine. Probably the most effective type tested… | ||
| img145 | Graph of oil flow through bearings versus R.P.M. and a discussion on overoiling when running light. | ||
| View original record | - 14 - Hs/ACL/T19.5.26. OIL FLOW THROUGH BEARINGS ON CAR 12 Ex. PRESS 17.5 - 27 LBS/口". OIL FLOW PTS/MIN. R.P.M. This probably represents a fairly good example but is a condition we can obtain on… | ||
| img146 | Page discussing engine lubrication, oil circulation, and consumption rates for a Phantom model. | ||
| View original record | - 13 - Hs/ACL/T19.5.26. greatest tendency to overoil. This at first sight may seem rather paradoxical but we must remember that a fixed spring is employed for each release valve and pressures below… | ||
| img147 | Report page discussing engine oil consumption, smoking exhaust, and the effect of engine speed on these issues. | ||
| View original record | - 15 - to the much lower flame temperature with large exhaust dilution being unable to cause complete combustion of the oil and resulting in a smoking exhaust which is not evident with high flame… | ||
| img148 | Summary of the factors that influence engine overoiling and methods to reduce it. | ||
| View original record | - 16 - SUMMARY OF FACTORS INFLUENCING OVEROILING. 1. Overoiling is usually evident by:- Excessive Oil Consumption and/or Smoky Exhaust when running light. 2. The chief factors are:- (a) Rate of Oil… | ||
| img149 | Method for measuring oil flow through engine bearings to diagnose an 'overoiler' car. | ||
| View original record | - 17 - Hs/ACL/T19.5.26. have the minimum (within the limits) clearance in the guides. The holes at the end of the inlet rockers are plugged to prevent excess oil pouring over the inlet valve. It may… | ||
| img150 | Test procedure to diagnose excessive oil flow in an engine by measuring the oil return rate. | ||
| View original record | - 18 - Hs/ACL/T19.5.26. be arranged for the test. It must be remembered that the oil supply to the gears and rockers must be stopped. Commence the test with the apparatus arranged as shewn in Fig. 4.… | ||
| img151 | Diagram showing the arrangement of apparatus for measuring oil flow through bearings. | ||
| View original record | ARRANGEMENT OF APPARATUS FOR MEASURING OIL FLOW THROUGH BEARINGS. FIG 4 DRAIN FROM SUMP MEASURING TANK B A OIL FROM RELEASE THERMOMETER START OF TEST LONG PIPE FROM SUCTION SIDE OF PUMP FIG 5 TAKE… | ||
| img152 | Blueprint showing the apparatus required for oil flow measurements. | ||
| View original record | B. B. USUAL RETURN TO CRANKCASE BLANKED. DRILLED THROUGH. PIPE ATTACHED. SECTION B.B. SUMP COVER. DRAIN PIPE. HOLE FOR SUCTION PIPE. LONGER SUCTION PIPE. ATTACHED TO PUMP. APPARATUS REQUIRED FOR OIL… | ||
| img153 | On steering heaviness caused by different tyre tread profiles and wear patterns on 40/50HP and 20HP models. | ||
| View original record | Hk. - Paris. Ps. Nice. Bombay. Pt. - Australia. Rv. ) Madrid. H. - Sales. BK. CWB. Sg. Whr. Br. - N. Mr. Evans. - Lillie Hall. Mr. Reid. - Glasgow. Mr. Bowring.School. P.O. Mr.Walker. D/BP. EVT. Mr.… | ||
| img154 | Index for a report on vibration-damping and shock-absorbing devices. | ||
| View original record | Dag8/10 recommendations VIBRATION-DAMPING AND SHOCK-ABSORBING DEVICES. ================================ I: INTRODUCTION. a. Qualification of the title. i. Smooth riding over small obstacles. ii.… | ||
| img155 | Introduction to vibration-damping and shock-absorbing devices, discussing the term 'Shock Absorbers' and common suspension faults. | ||
| View original record | Hs/Rml/T22.6.26. VIBRATION-DAMPING AND SHOCK-ABSORBING DEVICES. I: INTRODUCTION. a. Qualification of the title. There are large numbers of devices marketed to-day under the title of "Shock Absorbers".… | ||
| img156 | Explaining the reasons for adopting variable-rating suspension devices, focusing on an auxiliary coil spring system. | ||
| View original record | - 2 - II: VARIABLE-RATING SUSPENSION DEVICES. (a) Reasons for adoption. Owing to the internal friction of leaf springs, the suspension is harsh when riding over very small waves or irregularities such… | ||
| img157 | Page discussing the failings of auxiliary springs and proprietary hydraulic cushion accessories like J.M. and Thompson. | ||
| View original record | - 3 - Hs/Rml/T22.6.26. more smoothly over small obstructions at low speeds. For large spring deflections, the coil spring comes choc-a-bloc and the main spring functions in a normal manner. The… | ||
| img158 | Devices for increasing road spring rating, including auxiliary springs, and an analysis of longitudinal pitching at speed. | ||
| View original record | - 4 - Hs/Rm1/T22.6.26. (c) Devices for increasing road spring rating on max. bump. Some manufacturers prefer to fit the weakest possible leaf springs and to increase their rating for large deflections… | ||
| img159 | Page discussing suspension dynamics, inherent damping qualities of leaf springs, and mechanical friction dampers. | ||
| View original record | - 5 - with the natural period of the suspension, a large movement of the springs can easily be built up and the car body will undergo considerable displacement. It often happens on a wavy road at a… | ||
| img160 | Analysis of different types of shock dampers, including the 'Hartford' type and single-acting variable load dampers. | ||
| View original record | - 6 - Hs/Rml/T22.6.26. however, varies with the angle of the scissor arms and usually gives the least restraining force at max. spring deflection and the maximum when the spring extension is greatest.… | ||
| img161 | Page describing 'Snubbers' and introducing hydraulic shock dampers. | ||
| View original record | - 7 - Hs/Rm1/T22.6.26. their main attribute is that their connection to the axle can be a fabric strap. This eliminates a number of potential sources of wear and noise and in addition lubricating… | ||
| img162 | Page discussing the principles governing the flow of a viscous liquid through an orifice. | ||
| View original record | - 8 - Hs/Rml/T22.6.26. (ii) Those which have substantially a fixed minimum loading obtained by a spring retained valve opposing the circulation of a liquid. As a matter of interest it may be observed… | ||
| img163 | The principles and operation of 'Houdaille' type hydraulic shock dampers, including the effects of oil viscosity. | ||
| View original record | - 9 - Hs/Rm1/T22.6.26. start pitching are usually very rapid. (c) Dampers depending for their loading solely upon the orifice coefficient of a passage. Undoubtedly the best known hydraulic shock… | ||
| img164 | Viscosity curve for Price's Motorine C oil and discussion on its properties and use in Houdaille shock absorbers. | ||
| View original record | - 10 - Hs/Rm1/T22.6.26. VISCOSITY CURVE. PRICE'S MOTORINE C. OIL TEMP. C° TIME FOR OIL TO FLOW THROUGH AN ORIFICE SECS OR VISCOSITY. the viscosity of this oil is some five times that at 40°C. Now the… | ||
| img165 | Sectional diagram and explanation of a shock absorber, including a note on oil expansion. | ||
| View original record | - 11 - Hs/Rm1/T22.6.26. (ii) Though special ball valves are employed to keep the shock damper full, these are non-return and so no allowance is made for the expansion of the oil due to rise in temp.… | ||
| img166 | Page describing the Lovejoy hydraulic damper with a technical diagram. | ||
| View original record | - 12 - Hs/Rm1/T22.6.26. Exactly similar types of damper are the Derihon and the Berkshire and both suffer from the same disadvantages. (d) Dampers having fixed minimum loading obtained by spring… | ||
| img167 | Comparison of shock absorber designs, detailing the advantages and disadvantages of one type and introducing the R.R. damper. | ||
| View original record | - 13 - the suction valve at the base of the chamber allowing oil to flow into the cylinder. When the axle rebounds, the suction valve closes, being non-return, and oil is forced through the two spring… | ||
| img168 | Blueprint diagram and explanation of the oil flow within a piston assembly during operation. | ||
| View original record | - 14 - A is the high pressure side of the piston. When the piston moves towards A, in other words, when the axle moves away from the frame and the road spring rebounds, oil is forced out through the… | ||
| img169 | Page detailing road test results and operating principles for a superior damper design. | ||
| View original record | - 15 - of the piston from the reservoir R; a means of ejecting any air which may get behind the piston and cause lost movement, and a filter to clean the oil before it enters the high or low pressure… | ||
| img170 | Page describing the operation and adjustment of a shock absorber, including oil flow and potential troubles. | ||
| View original record | - 17 - Hs/Rm1/T22.6.26. pressure reaches a fixed amount, the low pressure valve N opens, allowing oil to flow through passages G to the high pressure end. When the road spring extends, and the axle… | ||
| img171 | Troubleshooting guide for a shock damper system, outlining potential causes and inspection points. | ||
| View original record | - 16 - Hs/Rml/T22.6.26. (i) Air has got into the system. In this case passage C should be inspected to see that this is not blocked up. (ii) The supply valves L are not working correctly. These should… | ||
| img172 | Index page for a document on the fundamentals of car suspension systems. | ||
| View original record | FUNDAMENTALS OF CAR PERFORMANCE. SUSPENSION. I. INTRODUCTORY. a. Measureable requirements of a good suspension. b. Difficulty of defining a 'well sprung' car from the passengers point of view. c.… | ||
| img173 | Introductory document on the principles and challenges of vehicle suspension design. | ||
| View original record | S U S P E N S I O N . 1. I. INTRODUCTORY. (a) Measureable requirements of a good suspension. Though there are a number of attributes in a desirable suspension which cannot be accurately defined,… | ||
| img174 | Page discussing the variables that affect the riding comfort of a car and the challenges in measuring it. | ||
| View original record | - 2 - the Colonies, each with their varying road surface. The second is the difficulty of measuring improvements. To enumerate a few of the variables which affect the riding of the R-R car:- (a)… | ||
| img175 | Page discussing the fundamental principles of suspension, focusing on the importance of low unsprung weight. | ||
| View original record | - 3 - criticism will probably be of increased value. On the whole the design and experimental departments are acutely aware of most of the short-comings of the R-R suspension. II: A FEW FUNDAMENTAL… | ||
| img176 | Spring deflection and the factors limiting spring flexibility in vehicle suspension design. | ||
| View original record | Hs/Rml/LG28.8.26. - 4 - of body work which is fitted to the chassis. This varies from a 5 cwts. sports 2-passenger body to a 14 cwts. Limousine 6-passenger body. It is obvious that the rear axle has… | ||
| img177 | Graph and accompanying text illustrating the effect of spring flexibility on ride comfort during upward acceleration. | ||
| View original record | - 5 - ROAD PROFILE. 2° UNIFORM ACCELERATION UPWARD. Graph Data: Y-Axis: UPWARD FORCE ON BODY ARBITRARY UNITS. (0, 100, 200, 300, 400, 500, 600) Lines: - INITIAL SPRING DEFLN. 1.625 - INITIAL SPRING… | ||
| img178 | Spring oscillation, natural frequency, and its effect on passenger comfort, including the formula for the period of a spring. | ||
| View original record | - 6 - Hs/Rm1/LG28.8.26. oscillation can be built up at a certain rate - say 80 impulses per minute. This rate of oscillation is known as the frequency of the rear springs, or the number of complete… | ||
| img179 | Graph and analysis of spring periodicity, plotting frequency against deflection to evaluate suspension characteristics. | ||
| View original record | - 7 - Graph 2. shews approximately the meaning of this formula expressed graphically. GRAPH 2. SPRING PERIODICITY. Y-AXIS: FREQUENCY PER MIN. X-AXIS: SPRING DEFLN INS. GRAPH DATA LABELS: PERIOD R.R.… | ||
| img180 | Page discussing the influence of the car's centre of gravity and the necessity for suspension damping, with a table comparing R-R and Sunbeam models. | ||
| View original record | - 8 - Hs/Rm1/LG28.8.26. When considering spring periodicity it should be remembered that, while the actual spring frequency is a guide to the behaviour of the car, the problem is much complicated by… | ||
| img181 | Vehicle suspension principles, focusing on conventional leaf spring systems. | ||
| View original record | - 9 - springs. For high speed work they are absolutely essential. A car arranged to perform well at high speed is very likely to ride like a truck at low speeds. A case in point is that of the Hispano… | ||
| img182 | The advantages and disadvantages of different vehicle suspension systems, including quarter elliptic springs. | ||
| View original record | - 10 - (i) Maximum lateral strength. (ii) Ease of attachment. (iii) No question of spring seat rotation. (IV) Lateral and torsional rigidity. (V) Ability to take torque reaction. (VI) Security against… | ||
| img183 | Page describing the characteristics and applications of various leaf spring designs for vehicle suspension. | ||
| View original record | - 11 - SAVING IN WEIGHT & ADDED SIMPLICITY. AXLE TILT PERMANENT SET EFFECT. REVERSE EFFECT WHEN BRAKING. The torque resisting capacity of a quarter elliptic spring can be increased by the substitution… | ||
| img184 | Page discussing the pros and cons of cantilever and transverse suspension systems, with an illustration. | ||
| View original record | - 12 - shocks and, although not so good as the semi-elliptic, presents a very fair resistance to rolling. It obviously saves a considerable amount of weight at the rear end of the frame. One… | ||
| img185 | Devices used to reduce internal friction in conventional leaf springs, including a product called 'Rectaskid'. | ||
| View original record | - 13 - necessitates some sort of torque control as on the Ford and 7 HP. Austin. IV: DEVICES USED IN CONJUNCTION WITH THE CONVENTIONAL LEAF SPRING. (a) Internal friction eliminators. From time to time… | ||
| img186 | Auxiliary spring devices and shock absorbers, including 'Alf's Button' and 'Nevajah'. | ||
| View original record | - 14 - rusts up and the balls tend to eat into the spring leaves. Messrs. Woodhead brought out a device known as 'Alf's Button' which was supposed to function on much the same lines as the… | ||
| img187 | Auxiliary springs, specifically the J.M. and Thompson types, and the development of fabric and rubber shackles. | ||
| View original record | - 15 - As the inter-leaf friction still remains with this device it is not very satisfactory for increasing low speed riding comfort. The other type of auxiliary spring is represented by the J.M. and… | ||
| img188 | The advantages and disadvantages of rubber and fabric spring shackles, with diagrams. | ||
| View original record | - 16 - Hs/Rml/LG28.8.26. Their main advantages are that they eliminate twelve lubricating points, maintain their silence, and wear well. Their disadvantages, that they spoil the low speed riding of… | ||
| img189 | Rebound devices and arrangements for increasing spring internal friction, with examples from Fiat and Woodhead. | ||
| View original record | - 17 - (d) Rebound devices and arrangements for increasing spring internal friction. A number of Continental cars have fitted rebound leaves to their springs; notably Alfa-Romeo, Lancia and Fiat. A… | ||
| img190 | Page discussing various types of leaf spring designs, including rebound and reversed leaves, for a Bentley. | ||
| View original record | - 18 - This clip is used with no less than four rebound leaves on the Bentley rear spring. Unfortunately the eyes in the spring leaves which hold the clip appear to be the weakest portion of the clip… | ||
| img191 | Analysis of Lancia Lambda leaf springs and a discussion on anti-rolling devices. | ||
| View original record | - 19 - a clip for every leaf as will be observed by the illustration of the Lancia rear spring. There are a number of other types of clip used to prevent the spring leaves separating on the re-bound,… | ||
| img192 | The principles of hydraulic anti-rolling devices and unconventional suspension systems. | ||
| View original record | - 20 - made as small as desired to give the required resistance to rolling. The same principle can be employed mechanically. PRINCIPAL OF HYDRAULIC ANTI-ROLLING DEVICE CHASSIS FRAME The objection to… | ||
| img193 | Diagram with a description of a Lancia-type suspension system. | ||
| View original record | 20 A LANCIA SUSPENSION DIAGRAM. SPRUNG WT. MOVING WITH CHASSIS. UNSPRUNG " " " WHEEL. A. MAIN SPRING. LOW RATING, LARGE INITIAL DEFLECTION, SMOOTH RIDING OVER SMALL BUMPS. B. AUXILIARY SPRING. HIGH… | ||
| img194 | Comparison of Lancia Lambda and Garson coil spring suspension systems, with a blueprint of the Garson system. | ||
| View original record | - 21 - (1) Lancia Lambda suspension. A diagram is given shewing the arrangement of coil spring and hydraulic damper in the Lancia front suspension. Apart from the riding qualities, which are very… | ||
| img195 | Page discussing the principles and advantages of air springing for rear wheel suspension, with a comparative graph. | ||
| View original record | - 22 - Hs/Rm1/LG28.8.26. For the rear wheel suspension by coil springs, however, where independent wheel springing is most difficult, something on these lines may eventually materialize commercially.… | ||
| img196 | The advantages and disadvantages of an air spring suspension system, including a blueprint diagram. | ||
| View original record | - 23 - It is meant to shew, however, that the air 'spring' is inherently suited to the absorption of small road inequalities while being still capable of keeping the axle off the buffers on bad roads.… | ||
| img197 | Blueprint drawings and specifications for front and rear leaf spring suspension systems. | ||
| View original record | - 24 - same results be obtained by a series of helical springs. At the moment the helical spring appears to offer the greater commercial possibilities. VI: SOME DETAILS OF THE R-R SUSPENSION SYSTEMS.… | ||
| img198 | Comparison of spring deflections, periodicities, tyre pressures, and shock damper settings for the 20 HP and 40/50 HP models. | ||
| View original record | - 25 - The main dimensions and clearances of the R-R 20 HP. and 40/50 HP. springs are indicated on the attached print. It will be noted that the deflections (static) of the 20 HP. springs are - front… | ||
| img199 | Front spring design and a table of riding complaints with their probable causes. | ||
| View original record | - 26 - There are two main reasons for this, one is the fact that it is necessary to keep the front of the car as low as possible for appearance, road holding and visibility from the driver's seat -… | ||
| img200 | Troubleshooting guide table for vehicle complaints, detailing potential causes related to front and rear suspension. | ||
| View original record | - 27 - Complaint. | Front suspension. | Rear suspension. Snatchy steering. Bumping in front. | Front springs or shock dampers weak. (Probably the latter) | Harsh riding in front only. | Shock dampers… | ||
| img201 | Diagrams and specifications for front and rear road springs for 20 HP and 40/50 HP models under 'Other Continental Conditions'. | ||
| View original record | OTHER CONTINENTAL CONDITIONS SECTION 1: 20 HP FRONT ROAD SPRING - F.53583 DIAGRAM TEXT: 1.950 +.300 -.300 CLEARANCE (FULL LOAD) BUFFER TO SPRING CLIPS. DIMENSIONS: 18.000, 20.000 SPECIFICATIONS:… | ||
| img202 | Specification drawing for 20 HP and 40/50 HP front and rear road springs for various export markets. | ||
| View original record | CONDITIONS FOR SPAIN, PORTUGAL, ITALY, POLAND & RUSSIA, AUSTRALIA, NEW ZEALAND, BRAZIL & S. AMER, AUSTRIA, EGYPT MALAY STATES, S. AFRICA Top Left Quadrant: 20 H.P. FRONT ROAD SPRING F 53583 1.950… | ||
| img203 | Springing chart for 40/50 HP cars prior to F.W.B., relating rear spring poundage to total vehicle weight. | ||
| View original record | POUNDAGE OF SPRING NEAR REAR. MAXIMUM TOTAL WEIGHT OF CAR COMPLETE WITH PASSENGERS & LUGGAGE SPRINGING CHART FOR ALL 40/50 H.P. CARS, PRIOR TO F.W.B. Chart line labels: 539 TO 1699 1700 TO 2099 2100… | ||
| img204 | Chart and instructions for determining front spring poundage based on total car weight. | ||
| View original record | INSTRUCTIONS. FIRST OBTAIN THE TOTAL WEIGHT OF THE CAR WITH MAXIMUM LOAD AS PER INSTRUCTIONS BELOW. THIS IS TO INCLUDE CHASSIS, BODY, SPARES, & ACCESSORIES & THE MAXIMUM NUMBER OF PASSENGERS FOR WHICH… | ||
| img205 | Graph of front and rear spring poundages against the maximum total weight of the car for the New Phantom model. | ||
| View original record | POUNDAGE OF NEARSIDE FRONT SPRING 1350 1325 1300 1275 1250 1225 1200 1175 1150 1125 1100 1075 FRONT SPRING REAR SPRING 5500 5600 5700 5800 5900 6000 6100 6200 6300 6400 6500 6600 MAXIMUM TOTAL WEIGHT… | ||
| img206 | Chart and instructions for determining vehicle spring poundage based on total weight for Australian chassis. | ||
| View original record | INSTRUCTIONS:- FIRST OBTAIN THE TOTAL WEIGHT OF THE COMPLETE CAR AS PER INSTRUCTIONS BELOW. THIS WEIGHT INCLUDES THE CHASSIS, BODY, SPARES, TOOLS, ACCESSORIES & THE TOTAL NUMBER OF PASSENGERS CARRIED.… | ||
| img207 | Fundamentals of car performance, detailing suspension issues and the concept of 'pitching' in the 40/50 HP model. | ||
| View original record | HS/Rml/LG20.12.27. FUNDAMENTALS OF CAR PERFORMANCE. 40/50 HP. SUSPENSION. We are aware that one of the most difficult problems encountered by outside inspectors at the moment is that of suspension. We… | ||
| img208 | Comparative analysis of the Lancia and 20 HP car designs, focusing on suspension and weight distribution to minimize pitching. | ||
| View original record | Cont'd. the wheel base and the maximum amount of weight each end. The car which conforms most nearly to these ideal conditions is the Lancia. The equivalent of the front axle is carried at the forward… | ||
| img209 | Vehicle pitching, wheelbase, and methods for improving ride quality through weight distribution. | ||
| View original record | -3- Actually, the fact that the 40/50 has a longer wheel base than the 20 HP. is a disadvantage for similar types of bodies. Briefly, as the wheel base of the modern car is more or less fixed at the… | ||
| img210 | Notes on suspension testing, body design trends, and addressing vehicle pitching issues. | ||
| View original record | -4- HS/Rm/LG20.12.27. wheels at the rear. Therefore, when making a test to show up the efficiency of the suspension always ensure that the petrol tank is full. While these notes may seem of rather a… | ||
| img211 | The fundamentals of car performance, specifically regarding acceleration and the effects of axle and compression ratios. | ||
| View original record | FUNDAMENTALS OF CAR PERFORMANCE. ACCELERATION The question sometimes arises as to the relative performance of various R-R models - also the effect of axle ratio and compression ratio on acceleration.… | ||
| img212 | Two graphs illustrating acceleration performance data for a 20 HP engine with different compression ratios and cut-out configurations. | ||
| View original record | Top Graph: ACCELERATION ACCELERATION FT/SEC/SEC. ROAD SPEED M.P.H. Legend: HIGH COMP. 20 H.P. HIGH COMP. 20 H.P. CUT OUT OPEN STANDARD 20 H.P. Bottom Graph: ACCELERATION HIGH V LOW COMPRESSION RATIO… | ||
| img213 | Two graphs comparing the acceleration performance of various vehicle configurations. | ||
| View original record | ACCELERATION ROLLS ROYCE V BENTLEY VELOCITY M.P.H. TIME SECONDS 6 1/2 LITRE BENTLEY 10 E.X. 15 TOOTH AXLE STANDARD PHANTOM. ALL FIGURES DIRECT DRIVE C.O. CLOSED. ACCELERATION HIGH V LOW AXLE RATIO… | ||
| img214 | Two acceleration graphs comparing different open touring cars and compression ratios. | ||
| View original record | Top Graph: ACCELERATION HIGH V LOW COMPRESSION RATIO 40/50 VELOCITY M.P.H. TIME SECONDS OPEN TOURING CARS - 10 E.X. WT EMPTY 2.27 TONS COMP RATIO 5.2/1 - 98 N.K. WT EMPTY 2.34 TONS COMP RATIO 4/1 10… | ||
| img215 | Amendment concerning the fitting of low-pressure tyres and the necessity of hydraulic shock dampers on 20 HP and 40/50 HP chassis. | ||
| View original record | Hk. - Paris. Ps. Nice. Bombay. Pt. - Australia. Hv. - Madrid. H. - Sales. Barlow Mews. CWB. Sg. Whr. Fr. - N. Mr. Evans - Lillie Hall. Mr. Reid - Glasgow. Mr. Bowring - School. D.O. - Mr. Walker.… | ||
| img216 | Investigation into various troubles and failures experienced with the 20 HP starter motor. | ||
| View original record | HK. - Paris. Ps. Nice. Bombay. Pt. - Australia. Rv. - Madrid. H. - Sales. Barlow Mews. CWB. Sg. Whr. Er. - N. Mr. Evans - Lillie Hall. Mr. Reid - Glasgow. Mr. Bowring. D.O. - Mr. Walker. F/EP. FWT.… | ||
| img217 | Analysis of cork clutch and starter pinion engagement failures and their resolution. | ||
| View original record | Cont'd. -2- Hm.59. Several cases have been found whereby the cork clutch had insufficient friction to convey the inertia of the mass of the unit, and would not run up the thread and so engage. The… | ||
| img218 | Investigation into starter unit slipping, with improvements made by adjusting spring loads and modifying a bush to prevent clutch oil contamination. | ||
| View original record | -3- Cont'd. Hm.59. During our tests we found that by increasing the spring D.51133 to 10 lbs. and reducing the spring D.51144 to 84 lbs. we obtained an all-round improvement of the starter unit. In… | ||