| Description | Date | Identifier | |
| Comparison of the connecting rod and piston assembly weights between a Pierce Arrow and a Phantom model. | 1st Jan 1928 | Box 23 \ 4 Scan013 | |
| Weights of Pierce Arrow reciprocating parts, duralumin connecting rods, and strut piston design. | 2nd Feb 1928 | Box 23 \ 4 Scan014 | |
| Letter from Maurice Olley in Springfield to Mr. Robotham in Derby regarding piston and connecting rod assemblies. | 25th Jan 1928 | Box 23 \ 4 Scan015 | |
| Viability of Bohnalite steel strut pistons and duralumin connecting rods. | 21th Feb 1928 | Box 23 \ 4 Scan016 | |
| Weight of piston and connecting rod parts, and the ordering of a set of Pierce-Arrow parts. | 23th Feb 1928 | Box 23 \ 4 Scan017 | |
| Correspondence from Rolls-Royce of America regarding an order for Pierce-Arrow engine components, detailing specifications and pricing. | 17th Mar 1928 | Box 23 \ 4 Scan018 | |
| Comparing the bore and crank pin diameter of Pierce Arrow parts to the company's 20 HP model. | 31th Mar 1928 | Box 23 \ 4 Scan019 | |
| Final report on the comparative cooling performance of the Phantom II against five other cars at Brooklands. | 25th Mar 1930 | Box 23 \ 4 Scan020 | |
| Comparative analysis of cooling system dimensions and vehicle performance against competitor cars. | 25th Aug 1930 | Box 23 \ 4 Scan021 | |
| Performance comparison and analysis of 25 HP and 20 HP models, including on-track speed test results. | 25th Aug 1930 | Box 23 \ 4 Scan022 | |
| Note on performance gains from a 112° camshaft and higher compression. | 25th Aug 1930 | Box 23 \ 4 Scan023 | |
| Comparative analysis of radiator and engine performance data for various car models. | 1st Sep 1930 | Box 23 \ 4 Scan024 | |
| Blueprint showing comparative acceleration figures and speedometer calibrations for various cars. | 1st Sep 1930 | Box 23 \ 4 Scan025 | |
| Comparative analysis table of motor car cooling system specifications and performance data. | 16th Oct 1928 | Box 23 \ 4 Scan026 | |
| Visits to Gleasons Works and Pierce Arrows in the U.S.A. to observe their manufacturing processes. | 4th Feb 1932 | Box 23 \ 4 Scan027 | |
| Suspension, braking, and power unit characteristics, with comparisons to other vehicles. | 4th Feb 1932 | Box 23 \ 4 Scan028 | |
| Page discussing intake silencers and rubber engine mountings, with a sketch of a Pierce-Arrow 'Hot Spot' exhaust system. | 4th Feb 1932 | Box 23 \ 4 Scan029 | |
| Diagram of a Pierce Arrow engine mounting and notes on their exhaust silencer. | 4th Feb 1932 | Box 23 \ 4 Scan030 | |
| Observations on a vehicle's steering, tappet adjustment, radiator, and gearbox systems. | 4th Feb 1932 | Box 23 \ 4 Scan031 | |
| Blueprint diagrams for a 'Pierce' self-adjusting tappet and crankshaft damper. | 4th Feb 1932 | Box 23 \ 4 Scan032 | |
| Viability of a Renault rotary engine design. | 15th Jul 1910 | Box 23 \ 4 Scan033 | |
| The performance issues of a Renault car, including ignition knock, carbon buildup, and poor carburation. | 30th Sep 1910 | Box 23 \ 4 Scan034 | |
| Petrol flow issues at slow speeds causing sooting and poor consumption. | 30th Sep 1910 | Box 23 \ 4 Scan035 | |
| Critical assessment of a 6-cylinder Renault model, detailing numerous mechanical faults. | 31th Mar 1911 | Box 23 \ 4 Scan036 | |
| Dangerously low steering lever and the subsequent test work to try and improve it. | 1st Feb 1911 | Box 23 \ 4 Scan037 | |
| Cylinder and piston clearance measurements for a Renault engine. | 5th Apr 1911 | Box 23 \ 4 Scan038 | |
| Dynamometer test results for a 6-cylinder Renault 80 x 120 engine. | 7th Apr 1911 | Box 23 \ 4 Scan039 | |
| Renault 14/20 HP chassis being sent for testing. | 19th Apr 1911 | Box 23 \ 4 Scan040 | |
| Technical notes on a Renault Car. | 1st Jun 1911 | Box 23 \ 4 Scan041 | |
| Potential patent royalty issues with Renault and Mercedes. | 1st Jun 1911 | Box 23 \ 4 Scan042 | |
| Record card detailing the testing and modification of a Renault type clutch. | 11th May 1911 | Box 23 \ 4 Scan043 | |
| Alterations to an experimental Renault clutch. | 17th Oct 1911 | Box 23 \ 4 Scan044 | |
| 50 HP Renault car, detailing its performance. | 1st Mar 1924 | Box 23 \ 4 Scan045 | |
| Secret memo discussing lag and sticking issues in an E.A.C. servo system, with proposed solutions and comparisons to Renault and Hispano systems. | 4th Jul 1924 | Box 23 \ 4 Scan046 | |
| Brake system shortcomings, a proposed ratchet drive improvement, and comparisons with competitor vehicles. | 28th Apr 1924 | Box 23 \ 4 Scan047 | |
| The design and construction of a 1922 Renault car, comparing it to pre-war models. | 29th Apr 1924 | Box 23 \ 4 Scan048 | |
| Patentability and technical differences of plate clutch servo systems, comparing Hispano, Renault, and an in-house design. | 1st Jun 1924 | Box 23 \ 4 Scan049 | |
| Renault acceleration curves and horsepower calculations. | 21th Mar 1925 | Box 23 \ 4 Scan050 | |
| Car performance, HP curves, and speedometer accuracy from external tests. | 21th Mar 1925 | Box 23 \ 4 Scan051 | |
| The inaccuracies of road tests published in motor journals due to speedometer reliability. | 21th Mar 1925 | Box 23 \ 4 Scan052 | |
| The difficulties of vehicle performance testing and analyzing a competitor's improbable acceleration curve. | 21th Mar 1925 | Box 23 \ 4 Scan053 | |
| Critiquing the accuracy of performance tests on a Renault car published in motoring magazines. | 21th Mar 1925 | Box 23 \ 4 Scan054 | |
| Analysis of braking curves, critiquing testing methods and comparing deceleration figures. | 23th Mar 1925 | Box 23 \ 4 Scan055 | |
| Brake efficiency and deceleration at various road speeds, including test data and a performance curve graph. | 23th Mar 1925 | Box 23 \ 4 Scan056 | |
| Criticizing braking figures and curves published in 'The Motor' magazine. | 23th Mar 1925 | Box 23 \ 4 Scan057 | |
| Page discussing the interpretation of braking test results and criticizing 'The Motor' tests. | 23th Mar 1925 | Box 23 \ 4 Scan058 | |
| Graph analysing the acceleration curves and required brake horsepower for a 45 HP Renault. | 3rd Feb 1925 | Box 23 \ 4 Scan059 | |
| Page with a red 'Print Room' library stamp. | 21th Mar 1928 | Box 23 \ 4 Scan060 | |
| Road test report on a 45 HP Renault, comparing its performance to a Phantom. | 6th Dec 1927 | Box 23 \ 4 Scan061 | |
| Road test report on a car's stability, shock absorbers, back axle, speedometer accuracy, and brakes. | 9th Dec 1927 | Box 23 \ 4 Scan062 | |
| Performance of a Renault car and challenging published figures and lap times at Brooklands. | 9th Dec 1927 | Box 23 \ 4 Scan063 | |
| Full R.A.C. report on the 15,000 miles Siddeley-Deasy trial, published in 'The Autocar' magazine. | 22th Jul 1911 | Box 23 \ 4 Scan064 | |
| Trial run of a 45/50 HP Siddeley vehicle. | 16th Dec 1911 | Box 23 \ 4 Scan065 | |
| Comparative analysis of a Siddeley car's performance against a Rolls-Royce, covering power, gearing, weight, and handling. | 1st Sep 1928 | Box 23 \ 4 Scan066 | |
| Comparative report on a Siddeley car, focusing on its engine and suspension. | 19th Aug 1909 | Box 23 \ 4 Scan067 | |
| Perspective section diagram of the Siddeley-Deasy clutch. | 21th Mar 1914 | Box 23 \ 4 Scan068 | |
| Comparing the performance of an 18 HP Armstrong-Siddeley against a Goshawk, covering handling, speed, hill-climbing, and mechanical systems. | 19th Apr 1922 | Box 23 \ 4 Scan069 | |
| Confidential report on a visit to Armstrong Siddeley Works to discuss their aero engine technology, specifically oiling systems. | 26th Feb 1932 | Box 23 \ 4 Scan070 | |
| Engine design and performance, focusing on oil consumption, supercharging, valve cooling, and fuel economy. | 26th Feb 1932 | Box 23 \ 4 Scan071 | |
| Observations on engine bearings, crankcases, airscrew blades, Imperial Airways machines, and compression ignition engines. | 26th Feb 1932 | Box 23 \ 4 Scan072 | |
| Direct fuel injection, nitriding cylinders, and gaining engine experience from commercial air services. | 11th Apr 1932 | Box 23 \ 4 Scan073 | |
| Letter from Armstrong Siddeley Motors Ltd. regarding the rescheduling of a works visit. | 11th Apr 1932 | Box 23 \ 4 Scan074 | |
| Short typed message confirming an appointment with Mr. Cantrill. | 12th Apr 1932 | Box 23 \ 4 Scan075 | |
| Purchase and trial of competitor vehicles such as Austro-Daimler, Stutz, Mercedes, Packard, and Lancia-Lambda. | 17th Oct 1927 | Box 23 \ 5 Scan001 | |
| Recommending the purchase and testing of a Stutz car, comparing it favourably to a Packard-8. | 24th Oct 1927 | Box 23 \ 5 Scan002 | |
| Request to arrange an extended trial of a Stutz car with a view to purchase. | 1st Nov 1927 | Box 23 \ 5 Scan003 | |
| Arrangement of a trial run for a Stutz Car. | 9th Nov 1927 | Box 23 \ 5 Scan004 | |
| Arranging the trial of a Stutz car. | 10th Nov 1927 | Box 23 \ 5 Scan005 | |
| Arrangement for the trial of a Stutz car at Barkers Showrooms. | 17th Nov 1927 | Box 23 \ 5 Scan006 | |
| Telegram arranging a test run on a new Stutz car. | 23th Nov 1927 | Box 23 \ 5 Scan007 | |
| Unsatisfactory new Stutz car and the subsequent acquisition of a demonstration model. | 24th Nov 1927 | Box 23 \ 5 Scan008 | |
| Letter from Warwick Wright Ltd. to the Experimental Department regarding an instruction book for a Stutz. | 28th Nov 1927 | Box 23 \ 5 Scan009 | |
| Letter to Mr. Ball at Warwick Wright Ltd. concerning a tappet knock and weak valve adjustment after receiving an instruction book. | 1st Dec 1927 | Box 23 \ 5 Scan010 | |
| Letter to Warwick Wright Ltd. requesting information on a recurring issue with loose valve gear on a Stutz car. | 1st Dec 1927 | Box 23 \ 5 Scan011 | |
| 20 HP car testing, competitor analysis of a Stutz, and queries on Phantom hydraulics and Chrysler engine mounts. | 2nd Dec 1927 | Box 23 \ 5 Scan012 | |
| Letter from an automobile distributor discussing overhead valve gear trouble on a Stutz car. | 3rd Dec 1927 | Box 23 \ 5 Scan013 | |
| Technical specifications for the 'New Safety' Stutz vehicle, including engine, weight, and dimensional data. | 6th Dec 1927 | Box 23 \ 5 Scan014 | |
| Letter to the Public Control Department requesting the transfer of a Stucz car registration book. | 10th Dec 1927 | Box 23 \ 5 Scan015 | |
| Blueprint of a flywheel or hub assembly featuring spoke-like structures and lever mechanisms. | 23th Dec 1927 | Box 23 \ 5 Scan016 | |
| Blank page with a 'Print Received' stamp. | 23th Dec 1927 | Box 23 \ 5 Scan017 | |
| Blueprint drawing of a connecting rod with dimensions. | 23th Dec 1927 | Box 23 \ 5 Scan018 | |
| Blueprint of a crankshaft with numbered parts and dimensions. | 23th Dec 1927 | Box 23 \ 5 Scan019 | |
| Blueprint showing the dimensions of a friction lining, noted as being for a Stutz vehicle. | 23th Dec 1927 | Box 23 \ 5 Scan020 | |
| Blueprint showing a circular retaining ring with three integrated clamps. | 23th Dec 1927 | Box 23 \ 5 Scan021 | |
| Blueprint of a multi-throw crankshaft with dimensional annotations. | 23th Dec 1927 | Box 23 \ 5 Scan022 | |
| Blank or faded page with a Print Room stamp in the bottom right corner. | 23th Dec 1927 | Box 23 \ 5 Scan023 | |
| The electrical equipment and dynamo for a Stutz car. | 16th Dec 1927 | Box 23 \ 5 Scan024 | |
| Technical description of a motor, detailing its brushes, commutator, and engagement mechanism. | 16th Dec 1927 | Box 23 \ 5 Scan025 | |
| Technical report detailing the switch, battery, and ignition system components. | 16th Dec 1927 | Box 23 \ 5 Scan026 | |
| The condition of the ignition system and a description of the vehicle's lighting. | 19th Dec 1927 | Box 23 \ 5 Scan027 | |
| Comparing the crankshaft stiffness of a Stutz car to the 40/50 HP and 20 HP models. | 19th Dec 1927 | Box 23 \ 5 Scan028 | |
| General specification document for the new Safety Stutz Car. | 20th Dec 1927 | Box 23 \ 5 Scan029 | |
| Engine design and performance issues discovered after a 3000-mile run, with details on the cylinder head. | 20th Dec 1927 | Box 23 \ 5 Scan030 | |
| Critical analysis of a cylindrical combustion head, valve gear, and spring design, including a blueprint diagram. | 20th Dec 1927 | Box 23 \ 5 Scan031 | |
| Specifications for valve springs and a detailed description of the camshaft assembly and its operation. | 20th Dec 1927 | Box 23 \ 5 Scan032 | |
| Description of the cylinder block, crankcase, crankshaft, and pistons. | 20th Dec 1927 | Box 23 \ 5 Scan033 | |
| Blueprint showing the principal dimensions and specifications for a Stutz crankshaft. | 16th Dec 1927 | Box 23 \ 5 Scan034 | |
| The reverse side of a document with faint, mirrored text and a purple date stamp. | 16th Dec 1927 | Box 23 \ 5 Scan035 | |
| Page detailing specifications for gudgeon pins, connecting rods, and camshaft drives, including a blueprint of a Stutz connecting rod. | 16th Dec 1927 | Box 23 \ 5 Scan036 | |
| Detailed description of the engine's chain drive and lubrication system. | 16th Dec 1927 | Box 23 \ 5 Scan037 | |
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