| Description | Date | Identifier | |
| New blueprints for a coachbuilder's body clearance template for the back axle of a 40/50 chassis. | 6th Dec 1920 | Box 50 \ 2 Scan203 | |
| Specification for 40/50 chassis clearances for boxes and wheels mounted in wells on the running boards. | 5th Dec 1922 | Box 50 \ 2 Scan204 | |
| Cold weather carburation issues leading to poor starting and running performance. | 13th Dec 1920 | Box 50 \ 3 Scan001 | |
| Note on the use of induction exhaust pipe jacketing or the 'hot spot' principle in American cars. | 15th Dec 1920 | Box 50 \ 3 Scan002 | |
| From Mr. Royce proposing an experiment for a hot spot induction system using exhaust gas on the 40/50 HP model. | 15th Dec 1920 | Box 50 \ 3 Scan003 | |
| Mr. Royce's suggestions for experiments on reheating the carburetion system for the 40/50 HP chassis to handle poor quality petrol. | 21th Dec 1920 | Box 50 \ 3 Scan004 | |
| Experimental modifications to a car provided for holiday testing. | 24th Dec 1920 | Box 50 \ 3 Scan005 | |
| The cold weather starting performance of Experimental Car 2.EX, detailing carburetter issues and suggesting improvements. | 29th Dec 1920 | Box 50 \ 3 Scan006 | |
| Methods for heating the carburation system on a 40/50 HP chassis, referencing Hupmobile and Marmon designs. | 3rd Jan 1921 | Box 50 \ 3 Scan007 | |
| Requesting experiments on the induction system using a mixture of petrol and paraffin to create bad fuel. | 8th Jan 1921 | Box 50 \ 3 Scan008 | |
| Experiments with an auxiliary carburettor and recommending against the adoption of the Master Primer. | 12th Jan 1921 | Box 50 \ 3 Scan009 | |
| Engine modifications required to run successfully on low-grade motor fuels. | 13th Jan 1921 | Box 50 \ 3 Scan010 | |
| Continued list of engine design requirements with a comparison table against American and European cars. | 1st Jan 1921 | Box 50 \ 3 Scan011 | |
| Article from 'The Motor' magazine about the design considerations for carburetor hot-spots to improve fuel vaporization. | 22th Dec 1920 | Box 50 \ 3 Scan012 | |
| Article discussing the Brewer hot-spot carburetion design and the introduction of American-made Kenyon cord tyres to the UK market. | 22th Dec 1920 | Box 50 \ 3 Scan013 | |
| Modifications to the car's induction system to better suit current petrol quality and winter conditions. | 24th Jan 1921 | Box 50 \ 3 Scan014 | |
| Issues related to faulty carburation and low-grade motor fuels. | 24th Jan 1921 | Box 50 \ 3 Scan015 | |
| Technical discussion on engine carburation, fuel distribution issues, and the effects of low-grade fuels. | 24th Jan 1921 | Box 50 \ 3 Scan016 | |
| Scheme for providing a hot spot on the tee joint of the 40/50 HP induction pipe. | 19th Feb 1922 | Box 50 \ 3 Scan017 | |
| Request to send a blueprint of a 40/50 HP Hot Spot Induction Pipe to Rolls-Royce of America. | 19th Feb 1921 | Box 50 \ 3 Scan018 | |
| Modifications to the 40/50 HP chassis to accommodate a lower grade of petrol. | 2nd Feb 1921 | Box 50 \ 3 Scan019 | |
| Continued memo discussing a cross-current heating scheme for the induction pipe to aid fuel vaporization. | 2nd Feb 1921 | Box 50 \ 3 Scan020 | |
| Investigation into the poor performance of post-war engines, specifically issues with the 40/50 chassis induction system and fuel distribution. | 24th Feb 1921 | Box 50 \ 3 Scan021 | |
| Technical memorandum detailing an investigation into throttle design differences, specifically the boss, and methods for correction. | 24th Feb 1921 | Box 50 \ 3 Scan022 | |
| Page discussing engine performance issues related to fuel distribution, throttle adjustment, and fuel quality. | 24th Feb 1921 | Box 50 \ 3 Scan023 | |
| Engine performance with low-grade petrol and experiments with hot-spots and induction systems. | 24th Feb 1921 | Box 50 \ 3 Scan024 | |
| Experiments on carburation and induction systems to accommodate lower-grade petrol. | 25th Feb 1921 | Box 50 \ 3 Scan025 | |
| Experimental modifications to engine induction and exhaust piping, detailing their effects on performance. | 25th Feb 1921 | Box 50 \ 3 Scan026 | |
| Experiments with induction pipes and hot spots to resolve engine carburation issues. | 3rd Mar 1921 | Box 50 \ 3 Scan027 | |
| Letter discussing difficulties with cold starting, comparing performance to American cars and detailing experimental solutions. | 3rd Mar 1921 | Box 50 \ 3 Scan028 | |
| Carburettor choker and primer schemes, and a proposal for a new air valve mechanism. | 19th Feb 1923 | Box 50 \ 3 Scan029 | |
| Letter discussing experiments on induction pipe heating to improve engine performance and prevent pre-ignition. | 5th Mar 1921 | Box 50 \ 3 Scan030 | |
| Letter discussing various methods tried for improving cold weather starting, including a choker scheme. | 6th Mar 1921 | Box 50 \ 3 Scan031 | |
| Sketch showing the arrangement of collector nozzles for a heated induction pipe. | 6th Mar 1921 | Box 50 \ 3 Scan032 | |
| Cover letter regarding heated induction pipes, referencing an attached letter from America and an article extract. | 13th Apr 1921 | Box 50 \ 3 Scan033 | |
| Letter to the Managing Director discussing the design of heated induction pipes in American engines. | 25th Mar 1921 | Box 50 \ 3 Scan034 | |
| Engine heating methods, including Vee engines, the Packard 'Fuelizer', and improving low-speed performance. | 25th Mar 1921 | Box 50 \ 3 Scan035 | |
| Various methods of applying heat to engine manifolds and induction pipes. | 25th Mar 1921 | Box 50 \ 3 Scan036 | |
| The necessity of heat for engine performance, summarizing results from tests on induction pipes and throttle pins. | 26th Mar 1921 | Box 50 \ 3 Scan037 | |
| Page from an automotive journal describing a flexible universal joint, automatic advance coupling, a lubrication system, and a window regulator. | 27th Jan 1921 | Box 50 \ 3 Scan038 | |
| Article from 'Automotive Industries' discussing methods for improving vehicle fuel economy and performance through testing and analysis. | 27th Jan 1921 | Box 50 \ 3 Scan039 | |
| Page from 'Automotive Industries' discussing engine compression ratios and constant-clearance aluminum pistons. | 27th Jan 1921 | Box 50 \ 3 Scan040 | |
| Article from an automotive journal discussing the design and testing of aluminum pistons and fuel vaporizers. | 27th Jan 1921 | Box 50 \ 3 Scan041 | |
| Technical article from 'Automotive Industries' magazine discussing improvements in engine intake manifold design and carburetor application. | 27th Jan 1921 | Box 50 \ 3 Scan042 | |
| Page from 'Automotive Industries' magazine showing various engine performance and characteristic curves with accompanying technical text. | 27th Jan 1921 | Box 50 \ 3 Scan043 | |
| Page from an automotive journal detailing engine component testing and comparative performance analysis. | 27th Jan 1921 | Box 50 \ 3 Scan044 | |
| Page from an automotive journal detailing engine performance characteristics with diagrams and graphs. | 27th Jan 1921 | Box 50 \ 3 Scan045 | |
| Analysis with graphs showing the effects of compression and axle gear ratios on engine performance and fuel economy. | 27th Jan 1921 | Box 50 \ 3 Scan046 | |
| Page from an automotive journal featuring articles on engine economy, the new Heine-Velox car, and Danish military aviation. | 27th Jan 1921 | Box 50 \ 3 Scan047 | |
| Article from an automotive industry publication discussing dealer-manufacturer relationships and business practices. | 6th Jan 1921 | Box 50 \ 3 Scan048 | |
| Article from 'Automotive Industries' about the new model Lexington car and its Ansted engine. | 6th Jan 1921 | Box 50 \ 3 Scan049 | |
| Page from 'Automotive Industries' magazine describing the Ansted engine and the Lexington model T chassis. | 6th Jan 1921 | Box 50 \ 3 Scan050 | |
| Article from 'Automotive Industries' detailing the features of an engine, including its valve timing, fuel vaporizer, and lubrication system. | 6th Jan 1921 | Box 50 \ 3 Scan051 | |
| Detail specifications and a longitudinal section diagram for the Model T Lexington Car and its Ansted engine. | 6th Jan 1921 | Box 50 \ 3 Scan052 | |
| Specification sheet detailing dimensions, materials, and other data for various automobile components. | 6th Jan 1921 | Box 50 \ 3 Scan053 | |
| Requesting the creation of three experimental sets of hot spot induction pipes for the 40/50 chassis. | 14th Apr 1921 | Box 50 \ 3 Scan054 | |
| Testing of a heated induction pipe based on a print from Springfield. | 4th Apr 1921 | Box 50 \ 3 Scan055 | |
| Methods for testing and improving engine induction pipe hot-spots. | 20th Apr 1921 | Box 50 \ 3 Scan056 | |
| Issues with piston ring leakage and fumes, alongside tests on induction and exhaust pipe modifications. | 20th Apr 1921 | Box 50 \ 3 Scan057 | |
| Modifications to an induction pipe with a hot spot, focusing on the branch pipe and exhaust box connections. | 20th Apr 1921 | Box 50 \ 3 Scan058 | |
| Design of the 40/50 HP hot spot induction pipe, specifically the use of non-continuous steel branch pipes. | 22th Apr 1921 | Box 50 \ 3 Scan059 | |
| Letter discussing gasoline distillation curves, fuel quality, and crankcase dilution. | 24th May 1921 | Box 50 \ 3 Scan060 | |
| Engine starting methods, comparing the use of pilot jets and chokers with American gasolines. | 24th May 1921 | Box 50 \ 3 Scan061 | |
| Cancellation of an extra air valve and quoting a report on gasoline quality. | 1st May 1921 | Box 50 \ 3 Scan062 | |
| Graph of distillation curves comparing various American gasolines and blends. | 1st May 1921 | Box 50 \ 3 Scan063 | |
| Graph comparing the distillation curves and specific gravities of various American gasolines and fuel mixtures. | 25th Nov 1919 | Box 50 \ 3 Scan064 | |
| Graph of American Gasoline Distillation Curves for various fuel types and specifications. | 25th Nov 1919 | Box 50 \ 3 Scan065 | |
| Study on the effect of different gasoline qualities on aviation engine performance. | 25th Nov 1919 | Box 50 \ 3 Scan066 | |
| Page from an automotive industry publication with articles on small displacement engines and transportation sales. | 27th Apr 1921 | Box 50 \ 3 Scan067 | |
| Design and application of hot spot induction pipes for a 40/50 HP chassis. | 27th Apr 1921 | Box 50 \ 3 Scan068 | |
| Carburettor modifications, cold weather operation, and the potential future use of paraffin carburettors. | 27th Apr 1921 | Box 50 \ 3 Scan069 | |
| Experimental instruction to produce and trial a new 'Hot Spot Induction Fitting' for the 40/50 chassis induction pipes. | 28th Apr 1921 | Box 50 \ 3 Scan070 | |
| Letter discussing cylinder wear and winter starting troubles related to Chassis 2PP. | 28th Apr 1921 | Box 50 \ 3 Scan071 | |
| Cold weather starting issues, the need for a choker or pilot jet, and subsequent engine wear. | 2nd May 1921 | Box 50 \ 3 Scan072 | |
| Letter from Rolls-Royce of America concerning the discovery of core sand in the throttle of chassis 45-AE. | 2nd May 1921 | Box 50 \ 3 Scan073 | |
| Letter from the Springfield, Mass. office concerning customer complaints about winter starting troubles and the development of a choker device. | 4th May 1921 | Box 50 \ 3 Scan074 | |
| Request to make three sets of parts from blueprints for a hot spot induction pipe experiment on a 40/50 chassis. | 5th May 1921 | Box 50 \ 3 Scan075 | |
| Requests from Mr. Platford for experimental reports and cable answers to be sent to Springfield. | 18th May 1921 | Box 50 \ 3 Scan076 | |
| Letter discussing a paper by G. B. Dorris on manifold design aimed at eliminating crankcase dilution. | 24th May 1921 | Box 50 \ 3 Scan077 | |
| Manifold design, carburetter placement, and comparative temperature readings for engine performance. | 26th May 1921 | Box 50 \ 3 Scan078 | |
| Springfield complaints regarding the 40/50 chassis, focusing on induction pipe heat and carburation issues. | 26th May 1921 | Box 50 \ 3 Scan079 | |
| Induction pipe experiments conducted on a 40/50 engine. | 26th May 1921 | Box 50 \ 3 Scan080 | |
| Petrol loading in the induction pipe, its causes, effects on engine performance, and related test results. | 26th May 1921 | Box 50 \ 3 Scan081 | |
| Testing the optimal position of a 'hot spot' on the induction pipe to improve fuel distribution in a multi-cylinder engine. | 26th May 1921 | Box 50 \ 3 Scan082 | |
| Tests of different induction and exhaust pipe configurations to improve heating. | 26th May 1921 | Box 50 \ 3 Scan083 | |
| Experiments testing various engine induction pipe designs to improve fuel distribution and performance. | 25th May 1921 | Box 50 \ 3 Scan084 | |
| Tests conducted on a hot spot pipe and throttle to improve fuel distribution. | 26th May 1921 | Box 50 \ 3 Scan085 | |
| Technical memo discussing modifications to the throttle and induction system to improve performance with lower grade fuels in cold conditions. | 26th May 1921 | Box 50 \ 3 Scan086 | |
| Test report on various induction pipe configurations and their effect on engine performance. | 12th Nov 1920 | Box 50 \ 3 Scan087 | |
| Horsepower tests and carburetion improvements for the Goshawk I engine. | 1st May 1921 | Box 50 \ 3 Scan088 | |
| Test report on the Goshawk I engine comparing a Stromberg carburetter to the standard R-R model, and an analysis of the induction system and steering. | 31th May 1921 | Box 50 \ 3 Scan089 | |
| Note on steering wobble adjustments and the performance of the Goshawk I exhaust system. | 1st May 1921 | Box 50 \ 3 Scan090 | |
| Explaining the cause of popping in the silencer on 40/50 HP cars when the throttle is shut. | 1st Jun 1921 | Box 50 \ 3 Scan091 | |
| Tests to diagnose the cause of explosions in the silencer. | 1st Jun 1921 | Box 50 \ 3 Scan092 | |
| Using a 'hot-spot' to reduce liquid petrol in the pipe and prevent explosions in the silencer. | 1st Jun 1921 | Box 50 \ 3 Scan093 | |
| Results of tests conducted on hot-spot induction pipes to improve engine torque and consumption. | 2nd Jun 1921 | Box 50 \ 3 Scan094 | |
| Recommendations for a new throttle casting and exhaust heating hot-spot system. | 18th Feb 1921 | Box 50 \ 3 Scan095 | |
| Extract detailing the fitment and planned simplification of a heated induction pipe for American production models. | 3rd Jun 1921 | Box 50 \ 3 Scan096 | |
| Extract discussing the performance and required modification of a new choke design. | 4th Jun 1921 | Box 50 \ 3 Scan097 | |
| Telegram confirmation regarding engine test results for a 'hot spot' heating method. | 4th Jun 1921 | Box 50 \ 3 Scan098 | |
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