| Description | Date | Identifier | |
| Design and interchangeability of tappets for the L.H. SS. Engine. | 22th Feb 1929 | West Wittering \ T \ January1929-February1929 Scan178 | |
| Two-level device for an Autovac system, including a diagram for a fuel tap. | 25th Feb 1929 | West Wittering \ T \ January1929-February1929 Scan179 | |
| Design options for a dashboard pump, specifically regarding valve opening and stopping mechanisms. | 22th Feb 1929 | West Wittering \ T \ January1929-February1929 Scan180 | |
| Secret memorandum discussing Mr. Elliott's investigation into different types of valve springs. | 28th Feb 1929 | West Wittering \ T \ January1929-February1929 Scan181 | |
| Preference for a three-lamp headlamp system over other options. | 23th Feb 1929 | West Wittering \ T \ January1929-February1929 Scan182 | |
| From 'R.' expressing a preference for smaller wheels (18-EX) and recalling past struggles with 20HP wheels. | 28th Feb 1929 | West Wittering \ T \ January1929-February1929 Scan183 | |
| Secret memorandum regarding a complaint about the too rapid opening of radiator shutters and a proposed modification. | 23th Feb 1929 | West Wittering \ T \ January1929-February1929 Scan184 | |
| Design considerations for four-seater all-weather car bodies, covering width, doors, riding comfort, lighting, horns, and colour schemes. | 23th Feb 1929 | West Wittering \ T \ January1929-February1929 Scan185 | |
| Suggestion for making tappets truly vertical in an engine, including a comparative sketch. | 23th Feb 1929 | West Wittering \ T \ January1929-February1929 Scan186 | |
| Whether to manufacture electrical accessories in-house or license designs from companies like Bosch. | 28th Feb 1929 | West Wittering \ T \ January1929-February1929 Scan187 | |
| Potential for in-house manufacturing or licensing of electrical accessories, specifically screen wipers and horns. | 23th Feb 1929 | West Wittering \ T \ January1929-February1929 Scan188 | |
| Modifying the front brake direct leverage system on a chassis lacking a gearbox countershaft. | 23th Feb 1929 | West Wittering \ T \ January1929-February1929 Scan189 | |
| Design of an SS Valve Gear Cover, focusing on noise reduction and material choice. | 25th Feb 1929 | West Wittering \ T \ January1929-February1929 Scan190 | |
| Carburetion, water circulation, throttle heating, and engine performance. | 25th Feb 1929 | West Wittering \ T \ January1929-February1929 Scan191 | |
| Comparison of valve gear oil pressures during warming up and normal running periods. | 25th Feb 1929 | West Wittering \ T \ January1929-February1929 Scan192 | |
| The maximum oil pressures for the 'SS' engine when starting from cold. | 19th Dec 1929 | West Wittering \ T \ January1929-February1929 Scan193 | |
| Proposed sling for the centre of a horizontal pipe in an SS exhaust system. | 26th Feb 1929 | West Wittering \ T \ January1929-February1929 Scan194 | |
| Secret memo regarding scheme 2843, detailing a stop for an SS. exhaust system's sliding joint. | 26th Feb 1929 | West Wittering \ T \ January1929-February1929 Scan195 | |
| Scheme for a hinged rear number plate and tail lamp assembly. | 26th Feb 1929 | West Wittering \ T \ January1929-February1929 Scan196 | |
| Engine mounting options, considering different feet designs, fabrication methods, and vibration issues. | 26th Feb 1929 | West Wittering \ T \ January1929-February1929 Scan197 | |
| Agreeing to test a new lubrication method for the valve gear, while commenting on the quiet performance of the current system. | 5th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan001 | |
| Design and operating pressure of a two-way press button starter switch, including proposed modifications. | 13th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan002 | |
| Modifications to improve starter motor lubrication, referencing blueprint LeC. 2683. | 14th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan003 | |
| Alternative methods for starter motor lubrication. | 18th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan004 | |
| The status and improvements of the electrical starters for the SS and 20HP models. | 25th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan005 | |
| Secret memo suggesting modifications to a press button starter switch to reduce its high operating pressure. | 2nd May 1929 | West Wittering \ T \ March1929-December1929 Scan006 | |
| Design improvements for an SS valve cover, including materials and manufacturing methods. | 5th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan007 | |
| The cornering stability of specimen 18-EX, with a safety warning against top-heavy cars. | 5th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan008 | |
| Modifications to the Phantom's spring gaiters and central oiling system. | 2nd Mar 1929 | West Wittering \ T \ March1929-December1929 Scan009 | |
| Secret memo discussing the arrangement of framed dashboard instruments, along with suggestions for coachbuilders and weight distribution. | 5th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan010 | |
| Chassis vibration periods, damping, and preventing engine torque from reaching the frame. | 4th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan011 | |
| Engine minutes and suggesting improvements to frame and suspension damping. | 4th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan012 | |
| Hand-drawn sketch of a component's cross-section with notes on alternative materials. | 5th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan013 | |
| Feasibility and challenges of adding a shutter control to the steering column. | 5th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan014 | |
| And comparing different gearbox designs and potential improvements. | 5th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan015 | |
| From 'R' discussing the decision to include grouped instruments for the SS and 20HP models. | 9th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan016 | |
| Potential improvements to the wheel carrier's set screw bolt for a 4-seater car. | 7th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan017 | |
| Change gear problems, discussing freewheel sideshafts, epicyclic 3rd speed gears, and patent applications. | 7th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan018 | |
| Technical comparison of front seat widths and door thicknesses for various coachwork models. | 7th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan019 | |
| Summary of recommendations and comparative measurements for car body dimensions, including doors and windows. | 7th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan020 | |
| Correspondence listing parts sent and providing assembly instructions for a 23-EX open body vehicle. | 7th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan021 | |
| Investigation into fitting tubular cross members to the SS frame to eliminate radiator 'shimmy'. | 3rd Nov 1929 | West Wittering \ T \ March1929-December1929 Scan022 | |
| The testing of SS. engine mountings, detailing road conditions and issues like radiator wobble and unsteadiness. | 12th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan023 | |
| Chassis wobble testing, exploring the effects of engine mounting and frame stiffness. | 12th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan024 | |
| Engine damping schemes (a) and (b), comparing different mounting methods including friction dampers and soft rubbers. | 12th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan025 | |
| Road wheel diameter, booming, roughness, and exhaust manifold tests, including a sketch of a manifold design. | 12th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan026 | |
| Testing vehicle exhausts, bodies, and frame schemes, noting issues with radiator joggles and steering. | 13th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan027 | |
| Comparing single and double crankshaft rear oil flinger designs to prevent oil leakage. | 13th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan028 | |
| Blueprints and design considerations for an SS oil base and filter, including component placement and oil capacity. | 14th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan029 | |
| The SS taper valve spring, discussing its current performance and proposed improvements. | 14th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan030 | |
| Standardisation of Morganite EG2 Brade brushes for 40/50 & 'SS' Dynamos as an alternative to Le Carbone brushes. | 14th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan031 | |
| Chassis periodicity issues and proposals for testing solutions on the 20HP & SS chassis. | 14th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan032 | |
| The design and necessary adaptations for a side wheel carrier for the 20HP chassis. | 18th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan033 | |
| Modifications to the hypoid rear axle casing to overcome distortion under load. | 19th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan034 | |
| Schemes for a freewheel in the sideshaft of the 20HP gearbox. | 20th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan035 | |
| Clarifying that an instruction for the Works regarding SS cars in France was sent to Mr. Royce in error. | 20th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan036 | |
| Clearance issues with the 'SS' Brake Cables and suggesting a modification to the expansion box. | 15th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan037 | |
| Proposals for a central lubrication reservoir for the rear axle and the 20HP front axle arrangement. | 22th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan038 | |
| Proposal for an SS. exhaust cutout control and toggle gear modifications. | 22th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan039 | |
| Proposal to temporarily fit a Phantom rear silencer to an SS car for experimental purposes. | 22th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan040 | |
| Relaying the contents of a telegram with feedback on vehicle frame and suspension modifications. | 22th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan041 | |
| With annotated diagrams detailing design modifications for a side wheel carrier. | 22th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan042 | |
| Unexpected trouble with the Phantom clutch, its intended use, and potential causes or solutions. | 28th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan043 | |
| Issues with hydraulic dampers and proposing the use of large free passage valves. | 25th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan044 | |
| Suggesting a comparative test of tapered versus parallel valve springs to assess superiority for periodic vibrations. | 25th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan045 | |
| Use of tubular cross members to increase chassis stiffness and addressing potential vibration issues. | 25th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan046 | |
| Cause of 'booming bodies' in cars, attributing the issue to coachbuilders. | 25th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan047 | |
| Various change-speed gearbox schemes, categorized by their effect on ease of gear change and operational silence. | 25th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan048 | |
| Comparative analysis of various gearbox and coupling mechanisms with their advantages and disadvantages. | 25th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan049 | |
| Comparison of the advantages and disadvantages of synchro-mesh and internal mesh with dog clutches gearboxes. | 25th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan050 | |
| Analysis of Warner, Detroit, and Stutz-Detroit gears, including a proposal by Mr. Royce for an epicyclic 3rd gear. | 26th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan051 | |
| Slight heating of a servo and the need for fabric testing before production. | 26th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan052 | |
| Modification of frame side members for the SS short chassis, by shortening the 150' wheelbase version. | 27th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan053 | |
| Scheme 2865 for centralised chassis lubrication, concerning the air vessels in the pivots of the 20HP front axle. | 27th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan054 | |
| Completion and return of schedules for an SS. Exhaust System. | 27th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan055 | |
| Proposal regarding centralised chassis lubrication, specifically turning the Bijur drip plug cap nut into a reservoir. | 27th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan056 | |
| Request to arrange a demonstration and test of the Salerni coupling. | 27th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan057 | |
| Secret memo detailing modifications and instructions for the production of an SS exhaust system and its components. | 28th Mar 1929 | West Wittering \ T \ March1929-December1929 Scan058 | |
| Issues with shock dampers and proposing improvements for ride quality. | 4th Apr 1929 | West Wittering \ T \ March1929-December1929 Scan059 | |
| Insufficient axle-body damping and steering wobble issues on a 20HP car. | 5th Apr 1929 | West Wittering \ T \ March1929-December1929 Scan060 | |
| Demonstration of the Salerni Coupling and anticipating potential issues with its performance. | 6th Apr 1929 | West Wittering \ T \ March1929-December1929 Scan061 | |
| The silencer system for the 20HP manifold, discussing potential designs and noise issues. | 6th Apr 1929 | West Wittering \ T \ March1929-December1929 Scan062 | |
| Secret memo regarding a Side Spare Wheel Carrier and the production of a longer engine foot. | 8th Apr 1929 | West Wittering \ T \ March1929-December1929 Scan063 | |
| 'R.' at Le Canadel agreeing to 'N. scheme 2560'. | 12th Apr 1928 | West Wittering \ T \ March1929-December1929 Scan064 | |
| Modification to the water circulation drainage pipe to improve drainage and address criticism. | 9th Apr 1929 | West Wittering \ T \ March1929-December1929 Scan065 | |
| Analysis of ignition plug overheating issues and proposed design modifications to improve water cooling. | 10th Apr 1929 | West Wittering \ T \ March1929-December1929 Scan066 | |
| Engine performance, focusing on cooler ignition plugs, compression ratios, and cylinder head modifications. | 11th Apr 1929 | West Wittering \ T \ March1929-December1929 Scan067 | |
| Suggestion to change the markings on an oil level indicator from quarter-gallon to half-gallon increments. | 11th Apr 1929 | West Wittering \ T \ March1929-December1929 Scan068 | |
| Proposing to use studs instead of screws for the SS Air Pump Assembly eccentric to overcome assembly difficulties. | 4th Dec 1929 | West Wittering \ T \ March1929-December1929 Scan069 | |
| Modifications to a 3rd speed easy change gearbox, complete with sketches. | 3rd Apr 1929 | West Wittering \ T \ March1929-December1929 Scan070 | |
| Cutter, a cage controlled by a narrow surface, and the fitting of a freewheel mechanism with a potential emergency cancelling device. | 13th Apr 1929 | West Wittering \ T \ March1929-December1929 Scan071 | |
| Foul condition with a gusset plate on the SS exhaust system and proposed design modifications. | 13th Apr 1929 | West Wittering \ T \ March1929-December1929 Scan072 | |
| Secret internal memorandum discussing 20HP car performance improvements by increasing the engine bore size. | 15th Apr 1929 | West Wittering \ T \ March1929-December1929 Scan073 | |
| Performance calculation comparing a 20HP model with the SS, considering engine capacity, weight, and axle ratio. | 16th Apr 1929 | West Wittering \ T \ March1929-December1929 Scan074 | |
| Weight reduction, body construction, and performance improvements for the future 20HP model. | 16th Apr 1929 | West Wittering \ T \ March1929-December1929 Scan075 | |
| Difficulty in dismantling the L.S. jet on the 20HP carburettor and proposing a design improvement. | 16th Apr 1929 | West Wittering \ T \ March1929-December1929 Scan076 | |
| Proposing an increase of the 20HP engine bore to 3.25 inches and discussing the technical implications. | 17th Apr 1929 | West Wittering \ T \ March1929-December1929 Scan077 | |
| Test report on the performance and drawbacks of a Salerni coupling fitted to a 7HP Fiat. | 17th Apr 1929 | West Wittering \ T \ March1929-December1929 Scan078 | |
| Secret memo regarding modifications to rear wheel carriers and associated special petrol tanks. | 17th Apr 1929 | West Wittering \ T \ March1929-December1929 Scan079 | |
| Confirmation letter detailing modifications to the cutout control, silencer, and heat shield. | 17th Apr 1929 | West Wittering \ T \ March1929-December1929 Scan080 | |
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