| Description | Date | Identifier | |
| List of points for consideration regarding the Bentley Overhead Camshaft Engine. | 8th Oct 1936 | Box 85 \ 3 scan0046 | |
| Technical memo suggesting the use of castellated nuts and noting the lack of a breather and thermometer pocket. | 8th Oct 1936 | Box 85 \ 3 scan0047 | |
| Features of a shorter duration valve lift curve camshaft for a Bentley cylinder head. | 18th Dec 1936 | Box 85 \ 3 scan0048 | |
| Page detailing modifications to camshaft and spring force specifications. | 12th Jan 1938 | Box 85 \ 3 scan0049 | |
| Urgent memo regarding the provision of Bentley Camshaft EB.3240 for the 'M' series. | 12th Jan 1938 | Box 85 \ 3 scan0050 | |
| Agreement to introduce an improved performance Bentley camshaft (EB.3240) into production for 'M' series cars. | 12th Jan 1938 | Box 85 \ 3 scan0051 | |
| Confirming the successful testing of engines with EB.3239 Cam Form camshafts and authorising the despatch of chassis. | 6th Sep 1938 | Box 85 \ 3 scan0052 | |
| Two designs for drilled up connecting rods for the Bentley and 20-HP models. | 15th Jul 1933 | Box 85 \ 3 scan0053 | |
| Improved design for connecting rod oil pipes for Bentley and 20-HP models. | 10th Jul 1933 | Box 85 \ 3 scan0054 | |
| Calculation on the effect on critical speed of using Duralumin connecting rods in a Bentley engine. | 23th Sep 1933 | Box 85 \ 3 scan0055 | |
| Request to weigh and measure Bentley RR.56 connecting rods and to see a sample before engine assembly. | 5th Oct 1933 | Box 85 \ 3 scan0056 | |
| The manufacture of Duralumin connecting rods for the RR.56 Bentley. | 9th Oct 1933 | Box 85 \ 3 scan0057 | |
| Letter from High Duty Alloys Ltd. concerning the production methods for RR.56 Connecting Rods for a Bentley Chassis. | 7th Oct 1933 | Box 85 \ 3 scan0058 | |
| The weights and clearances for new Bentley RR.56 connecting rods. | 11th Oct 1933 | Box 85 \ 3 scan0059 | |
| Graph showing the thermal expansion of the small and large end bores of an RR56 connecting rod. | 10th Oct 1933 | Box 85 \ 3 scan0060 | |
| Weight comparison of connecting rods for RR.56, Bentley, and 20/25 models. | 9th Oct 1933 | Box 85 \ 3 scan0061 | |
| Specifications for Bentley RR. 56 connecting rods, including clearances, lubrication, weight, and dimensions. | 16th Oct 1933 | Box 85 \ 3 scan0062 | |
| Particulars for connecting rods in R.R.56 forged aluminium alloy, referencing information from High Duty Alloys and Leyland Motors. | 23th Oct 1933 | Box 85 \ 3 scan0063 | |
| Letter from Leyland Motors to High Duty Alloys regarding clearances for R.R.56 connecting rods. | 15th Sep 1933 | Box 85 \ 3 scan0064 | |
| Confirming and comparing the weights of Bentley, 20/25, and RR.56 connecting rods. | 24th Oct 1933 | Box 85 \ 3 scan0065 | |
| Calculation on the effect of Dural connecting rods on the crankshaft critical speed for a Bentley engine. | 25th Oct 1933 | Box 85 \ 3 scan0066 | |
| Requested modification to a Damper Connecting Rod. | 10th Nov 1933 | Box 85 \ 3 scan0067 | |
| Inquiring about the halted production of forged aluminum connecting rods and the continuation of associated pistons and gudgeon pins. | 31th Jan 1934 | Box 85 \ 3 scan0068 | |
| Requesting the machining of a set of Dural connecting rods with specific modifications. | 24th Feb 1934 | Box 85 \ 3 scan0069 | |
| The machining of Dural connecting rods and the deletion of shims. | 26th Feb 1934 | Box 85 \ 3 scan0070 | |
| Design for Bentley Duralumin connecting rods with the shim removed. | 27th Feb 1934 | Box 85 \ 3 scan0071 | |
| Modifications required to test longer Bentley connecting rods made of Duralumin. | 28th Feb 1934 | Box 85 \ 3 scan0072 | |
| The requirements for fitting longer connecting rods to a Bentley Test Bed Unit. | 8th Mar 1934 | Box 85 \ 3 scan0073 | |
| Instructions regarding forged aluminium connecting rods for the 3 1/2 Litre Bentley. | 1st Mar 1934 | Box 85 \ 3 scan0074 | |
| Investigation into the effect of connecting rod length on Bentley engine performance, efficiency, and vibration. | 16th Mar 1934 | Box 85 \ 3 scan0075 | |
| Graph of inertia torque for a single Bentley cylinder at 4250 RPM, comparing different connecting rod lengths. | 1st Mar 1934 | Box 85 \ 3 scan0076 | |
| Graph showing the effect of varying connecting rod length on various engine performance metrics. | 15th Mar 1934 | Box 85 \ 3 scan0077 | |
| Graph showing piston side thrust at 4250 RPM for a standard 6-cylinder Bentley engine, comparing different connecting rod lengths. | 1st Mar 1934 | Box 85 \ 3 scan0078 | |
| Connecting rod failure on Unit B.6 and instructions for its subsequent rebuild with specific modifications. | 13th Apr 1934 | Box 85 \ 3 scan0079 | |
| Standardisation document for drilled up connecting rods to clean up the design and remove the outside oil pipe. | 29th Mar 1934 | Box 85 \ 3 scan0080 | |
| Summary of running tests on duralumin connecting rods and a decision to abandon further development. | 1st Apr 1934 | Box 85 \ 3 scan0081 | |
| The failure of a Duralumin connecting rod during a 100-hour endurance test on a Bentley B.6 unit. | 11th Apr 1934 | Box 85 \ 3 scan0082 | |
| Analysis of connecting rod cap failures on a Bentley unit, considering torsional vibration as a potential cause. | 12th Apr 1934 | Box 85 \ 3 scan0083 | |
| Summary report on the total experimental running of Dural Con. Rods for Bentley. | 12th Apr 1934 | Box 85 \ 3 scan0084 | |
| Test and usage log for various component sets, detailing performance, mileage, and failures. | 12th Apr 1934 | Box 85 \ 3 scan0085 | |
| Continuation page of a test report detailing the failure of two rods and the total running hours. | 12th Apr 1934 | Box 85 \ 3 scan0086 | |
| Photograph of a fractured connecting rod big end cap. | 12th Apr 1934 | Box 85 \ 3 scan0087 | |
| Photograph of a connecting rod that has failed, showing a fracture at the big end cap. | 12th Apr 1934 | Box 85 \ 3 scan0088 | |
| Photograph of a connecting rod cap. | 13th Apr 1934 | Box 85 \ 3 scan0089 | |
| Blueprint illustrating cracks found in the Duralumin connecting rod cap for a Bentley. | 13th Apr 1934 | Box 85 \ 3 scan0090 | |
| Specification sheet detailing clearances for Bentley connecting rods made of Duralumin. | 15th May 1934 | Box 85 \ 3 scan0091 | |
| Confirmation of connecting rod bolts stretching on Bentley engines and the need for them to be strengthened. | 31th Jul 1934 | Box 85 \ 3 scan0092 | |
| Request to manufacture a lighter trial version of a Bentley Drilled Connecting Rod. | 2nd Oct 1934 | Box 85 \ 3 scan0093 | |
| Instructing a change to all future Bentley drilled rods to a new, lighter specification (Hs.1539). | 11th Oct 1934 | Box 85 \ 3 scan0094 | |
| Instructing a design change for narrow pin connecting rods. | 12th Oct 1934 | Box 85 \ 3 scan0095 | |
| On the failure of connecting rod bolts in Bentley test bed units, mandating a strict replacement procedure. | 1st Jan 1935 | Box 85 \ 3 scan0096 | |
| Failure of Bentley connecting rod bolts and recommending a stronger replacement. | 1st Jan 1935 | Box 85 \ 3 scan0097 | |
| Increased diameter of Bentley connecting rod bolts and the associated drawing LeC.4281. | 3rd Jan 1935 | Box 85 \ 3 scan0098 | |
| Strength of Bentley connecting rods and a request to modify a set for testing. | 9th Feb 1935 | Box 85 \ 3 scan0099 | |
| Requesting modification of Bentley Light Con. Rods EX.17754 to drawing Hs.1886. | 4th Mar 1935 | Box 85 \ 3 scan0100 | |
| Bentley connecting rod failure and requesting a modified set with two locating tabs. | 27th May 1935 | Box 85 \ 3 scan0101 | |
| Requesting modifications to narrow pin connecting rods for a Bentley. | 28th May 1935 | Box 85 \ 3 scan0102 | |
| Big end bearing failure and proposed modifications to narrow pin crankshaft bearings. | 1st Jun 1935 | Box 85 \ 3 scan0103 | |
| 12-cylinder engine design, specifically crankshaft practice and the need for a larger slipper wheel and damper. | 1st Jun 1935 | Box 85 \ 3 scan0104 | |
| Big end loading in Bentley engines, comparing standard and large bore units. | 1st Jun 1935 | Box 85 \ 3 scan0105 | |
| Comparison of engine performance characteristics between a standard and large bore engine configuration. | 1st Jun 1935 | Box 85 \ 3 scan0106 | |
| Polar plot diagram of the inertia load on a Bentley engine crankpin at 5000 RPM. | 29th May 1935 | Box 85 \ 3 scan0107 | |
| Polar plot diagram illustrating the inertia loading on a Bentley connecting rod big end bearing at 5000 RPM. | 29th May 1935 | Box 85 \ 3 scan0108 | |
| Polar plot diagram showing the big end loading for a Bentley engine. | 30th May 1935 | Box 85 \ 3 scan0109 | |
| The cold temperature testing of Hall's Metal Bearings on a Bentley connecting rod assembly. | 21th Oct 1935 | Box 85 \ 3 scan0110 | |
| Cold temperature testing of Hall's Metal Bearings on a connecting rod assembly. | 21th Oct 1935 | Box 85 \ 3 scan0111 | |
| Cold temperature test on a Bentley Dural connecting rod and crankpin assembly. | 30th Oct 1935 | Box 85 \ 3 scan0112 | |
| Notification regarding new L.O.P. and details for a Large Bore Bentley Chassis connecting rod. | 26th Nov 1935 | Box 85 \ 3 scan0113 | |
| Issue of new and altered blueprints for the Bentley 25/30 HP Chassis Connecting Rod. | 10th Jan 1936 | Box 85 \ 3 scan0114 | |
| Request for the weights of the Bentley connecting rod assembly. | 13th Jan 1936 | Box 85 \ 3 scan0115 | |
| New design for Bentley connecting rods to prevent breakages by avoiding sharp corners and increasing metal. | 28th Apr 1936 | Box 85 \ 3 scan0116 | |
| Urgent instruction to replace composite steel and aluminium shims with RR.56 forged shims for 25/30 and Bentley connecting rods. | 29th Sep 1936 | Box 85 \ 3 scan0117 | |
| The fitting of new parts to a car, including con-rods, oil pump, servo cams, and an expansion box, and noting issues found. | 3rd Mar 1937 | Box 85 \ 3 scan0118 | |
| Bentley big end loadings, referencing an attached polar diagram. | 24th Apr 1937 | Box 85 \ 3 scan0119 | |
| Issues with the bedding of bearing metal in Bentley con rods and the need for filing. | 29th Jul 1937 | Box 85 \ 3 scan0120 | |
| Investigation into damaged Bentley connecting rods and bolt failures from depots. | 21th Aug 1937 | Box 85 \ 3 scan0121 | |
| Request for a full analysis of the cost of Phantom III and Bentley connecting rods. | 31th Jan 1938 | Box 85 \ 3 scan0122 | |
| Design and performance of the Bensport Induction Pipe. | 3rd Jun 1932 | Box 85 \ 4 scan0001 | |
| Design considerations for engine pipework to prevent fuel accumulation and ensure smooth mixture flow. | 3rd Jun 1932 | Box 85 \ 4 scan0002 | |
| Proposed modifications to a standard S.U. carburetter for air supply, silencing, and cleaning. | 27th Mar 1932 | Box 85 \ 4 scan0003 | |
| Design of Bensport induction pipes, focusing on oil collection issues and the positioning of safety blow-back valves. | 23th Sep 1932 | Box 85 \ 4 scan0004 | |
| Issuance of scheme LeC.3200 for testing, determining clearances and engine suspension modification. | 23th Sep 1932 | Box 85 \ 4 scan0005 | |
| Lack of communication about a scheme for making and fitting Bensport carburetter parts. | 27th Sep 1932 | Box 85 \ 4 scan0006 | |
| Arguing against sub-contracting the carburetter for the Bensport chassis, advocating for in-house production. | 27th Sep 1932 | Box 85 \ 4 scan0007 | |
| Carburettor supply and modifications required for the Bensport car. | 12th Dec 1932 | Box 85 \ 4 scan0008 | |
| Covering note for a sketch of an automatic mixture control for two S.U. carburetters, regarding Bensport J.1. | 12th Dec 1932 | Box 85 \ 4 scan0009 | |
| Requesting to decarbonise the engine and fit rear engine feet on car 19-G4 before it goes to Birmingham. | 16th Dec 1932 | Box 85 \ 4 scan0010 | |
| Request for modified drawings and the urgent production of two Bensport induction pipes. | 13th Jan 1933 | Box 85 \ 4 scan0011 | |
| Trial of the Heards Induction Balance for experimental testing on the Bensport. | 30th Jan 1933 | Box 85 \ 4 scan0012 | |
| Engine fuel distribution issues and experiments to improve carburettor performance. | 7th Feb 1933 | Box 85 \ 4 scan0013 | |
| Performance graph of BHP and BMEP vs RPM for a Unit C.9 engine with varying intake manifold restrictions. | 6th Feb 1933 | Box 85 \ 4 scan0014 | |
| Confirming a discussion and outlining proposed modifications for a carburetter and induction pipe. | 20th Feb 1933 | Box 85 \ 4 scan0015 | |
| Proposed design layout for a Bensport carburetter air intake and silencer. | 13th Mar 1933 | Box 85 \ 4 scan0016 | |
| The hot spot pipes and silencer for a Bensport Series 1 vehicle. | 25th Mar 1933 | Box 85 \ 4 scan0017 | |
| Covering memo for attached notes concerning a discussion on Bensport S.U. Carburetters following Mr Skinner's visit. | 8th Apr 1933 | Box 85 \ 4 scan0018 | |
| Visit regarding the design, materials, and finish of Bensport Carburetters. | 7th Apr 1933 | Box 85 \ 4 scan0019 | |
| Modifications to the throttle body and carburetter suction chamber cap. | 8th Apr 1933 | Box 85 \ 4 scan0020 | |
| Request to manufacture a modified set of induction pipes for testing purposes. | 19th Apr 1933 | Box 85 \ 4 scan0021 | |
| Request for a drawing for the Bensport induction pipes. | 19th Apr 1933 | Box 85 \ 4 scan0022 | |
| Blueprints for new experimental inlet pipes for the Bensport J.I. Chassis. | 28th Apr 1933 | Box 85 \ 4 scan0023 | |
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