| Description | Date | Identifier | |
| Faulty clutch found during a car test for chassis number B.4.JD. | 23th Dec 1936 | Box 85 \ 2 scan0313 | |
| Return of a lined friction plate from a 4¼-litre Bentley chassis for examination due to a slipping clutch. | 2nd Jan 1937 | Box 85 \ 2 scan0314 | |
| Request to cut ventilation holes in a clutch case from the Unit Test Beds. | 13th Feb 1937 | Box 85 \ 2 scan0315 | |
| Jaggering clutch found on chassis B.126.JD from Car Mart Stock. | 4th Mar 1937 | Box 85 \ 2 scan0316 | |
| Propshaft dampers for 25/30 and Bentley models. | 4th Mar 1937 | Box 85 \ 2 scan0317 | |
| Order for Bentley clutch facings from Ferodo. | 7th May 1937 | Box 85 \ 2 scan0318 | |
| Clutch driven disc from Borg & Beck Co. of America, requiring modification to fit a Bentley. | 11th May 1937 | Box 85 \ 2 scan0319 | |
| Cause and remedy for rattling Bentley clutch and brake pedals. | 13th May 1937 | Box 85 \ 2 scan0320 | |
| Order be passed to Borg & Beck for Bentley clutch plates. | 27th Jul 1937 | Box 85 \ 2 scan0321 | |
| Instruction to fit an American-made Long clutch plate with Thermoid facings to chassis 5.B.IV. | 29th Jul 1937 | Box 85 \ 2 scan0322 | |
| Comparison table of specifications for P.III, 25/30, and Bentley models, including clutch data and other metrics. | 1st Jul 1937 | Box 85 \ 2 scan0323 | |
| Specifications for a Single Plate 12.C.B. Clutch as supplied to Lincoln. | 14th Feb 1934 | Box 85 \ 2 scan0324 | |
| Letter from Long Manufacturing Co. regarding specifications for a 12' single plate clutch. | 20th Feb 1934 | Box 85 \ 2 scan0325 | |
| Instructions for facing off the hubs of five Bentley 10' clutch plates. | 7th Aug 1937 | Box 85 \ 2 scan0326 | |
| Testing and recommendations for Thermoid clutch facings on 25/30 and Bentley models. | 10th Sep 1937 | Box 85 \ 2 scan0327 | |
| Re-directing parts for a Bentley Clutch Servo to be fitted to a different chassis. | 3rd Oct 1937 | Box 85 \ 2 scan0328 | |
| New Thermoid Facing for the Bentley Clutch to cure 'jagger troubles'. | 14th Oct 1937 | Box 85 \ 2 scan0329 | |
| Request for details and supply department for materials for old type Bentley clutches. | 16th Oct 1937 | Box 85 \ 2 scan0330 | |
| Limited supply of Graphite Bronze Facings for 3 1/2 litre Bentley Clutches. | 21th Oct 1937 | Box 85 \ 2 scan0331 | |
| Works order for the supply of material for old type Bentley clutches to Bentley Motors (1931) Ltd. | 22th Oct 1937 | Box 85 \ 2 scan0332 | |
| Partial fulfilment of an order for material for old type Bentley clutches due to stock shortages. | 26th Oct 1937 | Box 85 \ 2 scan0333 | |
| Proposing a simple rig for testing clutch springs on 4¼ Litre Bentley & 25/30 models. | 8th Nov 1937 | Box 85 \ 2 scan0334 | |
| Confirming the standardisation of 10-inch Bentley clutch plates to use Thermoid facings. | 16th Nov 1937 | Box 85 \ 2 scan0335 | |
| Requesting an order for 20/25 and 3 1/2 litre clutch springs due to depleted stock in stores. | 19th Nov 1937 | Box 85 \ 2 scan0336 | |
| The standardisation of Thermoid clutch facings for the 4 1/4 Litre Bentley. | 23th Nov 1937 | Box 85 \ 2 scan0337 | |
| Despatch of 45 Bentley Clutch Plates to Borg and Beck for fitting Thermoid Facings. | 24th Nov 1937 | Box 85 \ 2 scan0338 | |
| The supply and specification of 10' Thermoid faced clutches for Bentley vehicles. | 26th Nov 1937 | Box 85 \ 2 scan0339 | |
| Request to prepare two S/M rings for testing the 20/25 and 3 1/2 litre clutch. | 6th Dec 1937 | Box 85 \ 2 scan0340 | |
| Instructions for fitting new parts to a 20/25 & 3 1/2 litre clutch after a '1000 slip' test. | 8th Dec 1937 | Box 85 \ 2 scan0341 | |
| The dynamometer testing of Graphite Bronze Clutch Facings for 20/25 and 3½ litre Bentley models. | 13th Dec 1937 | Box 85 \ 2 scan0342 | |
| Results of clutch reliability and wear tests using different facing materials. | 13th Dec 1937 | Box 85 \ 2 scan0343 | |
| Test report on clutch modifications, comparing Ferodo and Graphite Bronze facings. | 13th Dec 1937 | Box 85 \ 2 scan0344 | |
| The testing of clutch facings, recommending the continued use of Graphite Bronze facings for 20/25 and 3 1/2 litre Bentley models. | 13th Dec 1937 | Box 85 \ 2 scan0345 | |
| Graph plotting the wear of different driving face materials against the number of slips. | 9th Dec 1937 | Box 85 \ 2 scan0346 | |
| The mileage of Thermoid faced clutches in experimental Bentley cars. | 12th Jan 1938 | Box 85 \ 2 scan0347 | |
| New part number for Graphite Bronze clutch facings for the 20/25 HP & 3½-Litre models. | 22th Jan 1938 | Box 85 \ 2 scan0348 | |
| Request to prepare parts for a Bentley 10' Clutch with Centrifugal Assistance. | 26th Jan 1938 | Box 85 \ 2 scan0349 | |
| Inquiring about wear and slack found in the bush for the 20/25 HP and Bentley clutch. | 25th Feb 1938 | Box 85 \ 2 scan0350 | |
| Chasing the completion of parts for a Bentley 10' centrifugal assistance clutch. | 15th Mar 1938 | Box 85 \ 2 scan0351 | |
| Instruction to fit a 10' Borg & Beck clutch with Centrifugal Assistance to a car. | 18th Mar 1938 | Box 85 \ 2 scan0352 | |
| Requesting an order for a 10 C.F. Clutch for experimental work on a Bentley. | 19th Mar 1938 | Box 85 \ 2 scan0353 | |
| Fitting of heavier weights for centrifugal clutch assistance. | 5th May 1938 | Box 85 \ 2 scan0354 | |
| Instructions for preparing a modified flexible flywheel for a Wraith or Bentley model, detailing parts and modifications. | 3rd Jun 1938 | Box 85 \ 2 scan0355 | |
| Requesting facilities to change the springs in several 10' Bentley clutches as a temporary measure. | 29th Jun 1938 | Box 85 \ 2 scan0356 | |
| Modification of Bentley clutches by replacing black springs with green ones to correct excessive pedal pressure. | 29th Jun 1938 | Box 85 \ 2 scan0357 | |
| Letter to Borg & Beck Company Ltd. regarding the spring poundage for a 10' Bentley clutch. | 29th Jun 1938 | Box 85 \ 2 scan0358 | |
| Letter from Borg & Beck Co. Ltd. discussing clutch spring modifications due to excessive pedal pressure. | 29th Jun 1938 | Box 85 \ 2 scan0359 | |
| Discrepancy with a 10' clutch spring's working length and thrust rate. | 4th Jul 1938 | Box 85 \ 2 scan0360 | |
| Letter from Borg & Beck Company Ltd regarding a change in thrust spring pressure for a Bentley 10.A3 clutch. | 4th Jul 1938 | Box 85 \ 2 scan0361 | |
| Investigation into faulty Bentley clutch springs from an outside supplier causing excessive pedal loading. | 5th Jul 1938 | Box 85 \ 2 scan0362 | |
| Discovery and resolution of an incorrect spring thrust issue on the Bentley clutch. | 11th Jul 1938 | Box 85 \ 2 scan0363 | |
| Drilling angle of oil drain holes for 25/30 & Bentley flywheels. | 29th Aug 1938 | Box 85 \ 2 scan0364 | |
| Note regarding clutch plates fitted with Thermoid for Phantom III, 125/30 and Bentley models. | 21th Oct 1938 | Box 85 \ 2 scan0365 | |
| Rig setup and dimensions for setting clutch fingers on Wraith and Bentley cars. | 24th Jan 1939 | Box 85 \ 2 scan0366 | |
| Requesting parts for a relay clutch mechanism and B.II engine oil pump for testing. | 11th May 1939 | Box 85 \ 2 scan0367 | |
| Technical memo discussing new engine timing and modifications for the Bensport power unit. | 23th Jan 1933 | Box 85 \ 3 scan0001 | |
| Request to manufacture a new camshaft for the Bensport Unit by scaling down existing 'R' engine cam designs. | 21th Mar 1933 | Box 85 \ 3 scan0002 | |
| Requirement of a new cam form for a Bensport Camshaft on the 'R' engine. | 3rd Apr 1933 | Box 85 \ 3 scan0003 | |
| Blueprint showing camshaft timing, dimensions, and cam lift data. | 3rd Apr 1933 | Box 85 \ 3 scan0004 | |
| The incorrect timing of a Bensport J.1 camshaft balancing cam and requesting a drawing alteration. | 4th Sep 1933 | Box 85 \ 3 scan0005 | |
| Correcting the angle on a Bensport Balancing Cam drawing. | 11th Sep 1933 | Box 85 \ 3 scan0006 | |
| Drawing for an increased oil well in the Bentley Balancing Cam housing. | 30th Sep 1933 | Box 85 \ 3 scan0007 | |
| Valve gear noise, automatic tappet adjustment, and potential camshaft modifications. | 11th Dec 1933 | Box 85 \ 3 scan0008 | |
| Investigation into the cause of Bentley tappet noise and various attempts to reduce it. | 11th Dec 1933 | Box 85 \ 3 scan0009 | |
| Analysis of valve and cam operation to determine velocities for quiet engine performance. | 11th Dec 1933 | Box 85 \ 3 scan0010 | |
| Analysis of cam contours, clearances, and their effect on tappet noise and valve velocity. | 11th Dec 1933 | Box 85 \ 3 scan0011 | |
| Table of maximum clearances and velocities for quiet cam operation for Cylinders No.1 and No.2. | 11th Dec 1933 | Box 85 \ 3 scan0012 | |
| Graph of valve lift against crankshaft degrees for a Bentley No.1 cylinder inlet cam. | 29th Sep 1939 | Box 85 \ 3 scan0013 | |
| Blueprint graph detailing the performance of Bentley Cam Toes, plotting valve lift against crankshaft degrees. | 29th Sep 1939 | Box 85 \ 3 scan0014 | |
| Blueprint graph showing valve lift characteristics against crankshaft degrees for Bentley Cam Toes. | 29th Sep 1939 | Box 85 \ 3 scan0015 | |
| Graph plotting valve lift against crankshaft degrees for Bentley cam toes on a B7 No.2 cylinder exhaust cam. | 29th Sep 1939 | Box 85 \ 3 scan0016 | |
| Blueprint graph of Bentley cam base circle contours for Unit B7. | 1st Jan 1940 | Box 85 \ 3 scan0017 | |
| Graph comparing standard and suggested Bentley cam toe profiles, lift, and velocities against crankshaft degrees. | 1st Jan 1940 | Box 85 \ 3 scan0018 | |
| Request to put in hand a camshaft to drawing Hs.1260 for slow running experiments on a Test Bed engine. | 4th Jan 1934 | Box 85 \ 3 scan0019 | |
| Letter from Rudge-Whitworth discussing valve timing and cam acceleration figures. | 17th May 1934 | Box 85 \ 3 scan0020 | |
| Page two of a letter to Rudge-Whitworth, Ltd. regarding a 500 c.c. racing engine. | 17th May 1934 | Box 85 \ 3 scan0021 | |
| Calculations for engine rocker ratio, cam and valve acceleration. | 24th May 1934 | Box 85 \ 3 scan0022 | |
| Letter to Rudge Whitworth Ltd. detailing the maximum positive acceleration of a Bentley camshaft. | 24th May 1934 | Box 85 \ 3 scan0023 | |
| Letter to G.L. Hack of Rudge-Whitworth Ltd. regarding camshaft particulars and hydraulic tappet adjuster blueprints. | 19th May 1934 | Box 85 \ 3 scan0024 | |
| Blueprint of a valve tappet block assembly with cross-sections and notes. | 19th May 1924 | Box 85 \ 3 scan0025 | |
| Blueprint of a cylindrical mechanical component with internal features. | 19th May 1934 | Box 85 \ 3 scan0026 | |
| Graph comparing valve overlap and timing positions for various engines. | 30th Jun 1934 | Box 85 \ 3 scan0027 | |
| Notification regarding the breakage of tappet springs on Bentley & 20/25 balance cams. | 30th Jun 1934 | Box 85 \ 3 scan0028 | |
| Overhead camshaft with a silent drive, referencing the eccentric drive on a 4-litre Bentley. | 9th Oct 1934 | Box 85 \ 3 scan0029 | |
| Letter from Michigan Tool Company regarding the use of Cone type worm gears for a proposed overhead camshaft. | 2nd Nov 1934 | Box 85 \ 3 scan0030 | |
| Letter from Michigan Tool Company regarding gear design and thread spacing. | 2nd Nov 1934 | Box 85 \ 3 scan0031 | |
| Letter to The Michigan Tool Company discussing requirements for an overhead camshaft drive using Cone worms. | 21th Nov 1934 | Box 85 \ 3 scan0032 | |
| Concluding page of a letter discussing two leading British manufacturers. | 21th Nov 1934 | Box 85 \ 3 scan0033 | |
| Design and modification of silent tappets for the Bentley. | 5th Dec 1934 | Box 85 \ 3 scan0034 | |
| List of design features for Cadillac tappets intended for use in a Bentley. | 1st Dec 1934 | Box 85 \ 3 scan0035 | |
| New camshaft design and timing for a Bentley engine to be used with silent tappets. | 4th Dec 1934 | Box 85 \ 3 scan0036 | |
| Letter from Michigan Tool Company regarding a Cone Type Worm Gear. | 20th Dec 1934 | Box 85 \ 3 scan0037 | |
| Graph comparing the Brake Mean Effective Pressure curves of various Cadillac and Rolls-Royce products. | 3rd Nov 1932 | Box 85 \ 3 scan0038 | |
| New camshaft for Bentley cars, its suitability for supercharged models, and related drawing numbers. | 14th Feb 1935 | Box 85 \ 3 scan0039 | |
| Summary table of cam forms, detailing specifications for various engines. | 1st Apr 1935 | Box 85 \ 3 scan0040 | |
| Request to produce a modified Bentley Camshaft (EB.2258) with two keyways. | 1st Apr 1935 | Box 85 \ 3 scan0041 | |
| Request to try an R. engine type camshaft in a 3.500 Bore Bentley and have the tappets Fescolised. | 3rd Oct 1935 | Box 85 \ 3 scan0042 | |
| Distributing blueprints for a Large Bore Bentley Camshaft and associated parts. | 26th Nov 1935 | Box 85 \ 3 scan0043 | |
| Request for the manufacture of two different camshafts for a Bentley (High Power) engine. | 5th May 1936 | Box 85 \ 3 scan0044 | |
| Instructions for an extra keyway to be cut on a shaft and a reference to camshaft arrangement details. | 5th May 1936 | Box 85 \ 3 scan0045 | |
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