| Description | Date | Identifier | |
| List of five potential cost-saving measures for crankshaft manufacturing, comparing options and their impact on factory cost. | 17th Jun 1939 | Box 8 \ 5 05-page66 | |
| Ordering Wraith cylinder liners and piston rings from Messrs. Hepworth & Grandage. | 4th May 1937 | Box 8 \ 6 06-page01 | |
| Arrangement and proposed testing of coolant jets for the Wraith III cylinder head. | 5th May 1937 | Box 8 \ 6 06-page02 | |
| Modifications to a Wraith Cylinder Head drawing. | 21th May 1937 | Box 8 \ 6 06-page03 | |
| Technical note on the interchangeability of a modified head. | 8th Jul 1937 | Box 8 \ 6 06-page04 | |
| Oil consumption performance of the Wraith loose liner cylinder block. | 8th Jul 1937 | Box 8 \ 6 06-page05 | |
| Oil consumption for car GWN 2. | 2nd Jul 1937 | Box 8 \ 6 06-page06 | |
| Record of oil consumption for car GAN 54. | 2nd Jul 1937 | Box 8 \ 6 06-page07 | |
| Proposal to modify the cylinder core vents on the Wraith III model by lowering the vent hole plugs. | 18th Sep 1937 | Box 8 \ 6 06-page08 | |
| Recommendation to modify cylinder core vents for the Wraith, Bentley, and 25/30 HP cylinder blocks. | 25th Sep 1937 | Box 8 \ 6 06-page09 | |
| Blueprint for a modified cylinder core vent for the Wraith II model. | 17th Sep 1937 | Box 8 \ 6 06-page10 | |
| Modified cylinder core vent for the Wraith, considering its application to the Bentley and 25/30 models. | 30th Sep 1937 | Box 8 \ 6 06-page11 | |
| The incorporation of vent plugs to reduce porosity and scrap in cylinder block castings. | 30th Sep 1937 | Box 8 \ 6 06-page12 | |
| Notification of drawing and part changes for the Wraith III Chassis cylinder section. | 30th Sep 1937 | Box 8 \ 6 06-page13 | |
| Continuation page of instructions regarding the dispatch of six sets of parts to L.O.P. | 30th Sep 1937 | Box 8 \ 6 06-page14 | |
| Instructions regarding new drawings and the production of parts for Wraith III Chassis water connections. | 30th Sep 1937 | Box 8 \ 6 06-page15 | |
| Request to produce a modified Wraith III cylinder head with different inlet and exhaust valve specifications. | 18th Nov 1937 | Box 8 \ 6 06-page16 | |
| Order for six cylinder head joints for the Wraith III model. | 16th Dec 1937 | Box 8 \ 6 06-page17 | |
| Confirming a telephone conversation regarding the urgent production of two Wraith cylinder blocks. | 8th Jan 1938 | Box 8 \ 6 06-page18 | |
| Wraith cylinders and high engine mounting for the EW.1580 cylinder blocks. | 10th Jan 1938 | Box 8 \ 6 06-page19 | |
| Request to machine 6 Wraith cylinder liners from Phosphor-Chrome material for bore wear tests. | 11th Jan 1938 | Box 8 \ 6 06-page20 | |
| Modification to the Wraith III cylinder head to create a venturi shape in the inlet ports. | 11th Jan 1938 | Box 8 \ 6 06-page21 | |
| Blueprints for a Wraith III cylinder head modification to create a venturi shape. | 11th Jan 1938 | Box 8 \ 6 06-page22 | |
| Recommendation to incorporate the boss for the raised engine mounting on future Wraith cylinder block castings. | 12th Jan 1938 | Box 8 \ 6 06-page23 | |
| The casting of experimental Wraith cylinder blocks and associated costs. | 28th Jan 1938 | Box 8 \ 6 06-page24 | |
| On the difficulty of removing the cylinder head on the Wraith and a proposed modification to the fan assembly. | 8th Feb 1938 | Box 8 \ 6 06-page25 | |
| Three modification schemes for the Wraith III cylinder head to prevent valve seat warping. | 30th May 1938 | Box 8 \ 6 06-page26 | |
| Schemes for the Wraith lll and the shared use of its cylinder head with Bentley models. | 30th May 1938 | Box 8 \ 6 06-page27 | |
| Comparative list of the number of engine parts for the Wraith and Phantom III models. | 16th May 1938 | Box 8 \ 6 06-page28 | |
| Parts quantity comparison table for the Phantom III and Wraith III models. | 27th May 1938 | Box 8 \ 6 06-page29 | |
| Urgent instruction to modify a Wraith cylinder head to address valve seat warping. | 27th May 1938 | Box 8 \ 6 06-page30 | |
| Urgent memo requesting modifications to the exhaust valve seats on a Wraith cylinder head. | 31th May 1938 | Box 8 \ 6 06-page31 | |
| Modification of Wraith cylinder heads and valves, including comparisons to Phantom III components. | 31th May 1938 | Box 8 \ 6 06-page32 | |
| Request to produce four modified Wraith III cylinder heads with smaller valves to test improvements on valve seat warping. | 27th Jun 1938 | Box 8 \ 6 06-page33 | |
| Request to cast 12 liners for a Wraith engine to drawing EW.1000. | 8th Jul 1938 | Box 8 \ 6 06-page34 | |
| Index card concerning a cylinder block for W.III and B.III models, with a cross-reference to another file. | 19th Sep 1938 | Box 8 \ 6 06-page35 | |
| Requesting the inclusion of modified cylinder blocks for Phantom III & Wraith III units. | 9th Sep 1938 | Box 8 \ 6 06-page36 | |
| Investigation into cracks found in a Wraith model cylinder head. | 14th Sep 1938 | Box 8 \ 6 06-page37 | |
| Valve seat failures in Wraith and Bentley cylinder heads and outlining production recommendations. | 14th Sep 1938 | Box 8 \ 6 06-page38 | |
| Modifications to the cylinder head gasket for the B.111 and Wraith cylinder block. | 15th Sep 1938 | Box 8 \ 6 06-page39 | |
| To hold production of Wraith cylinder heads due to cracked valve seats. | 16th Sep 1938 | Box 8 \ 6 06-page40 | |
| Modification to the cylinder block boss for the bye-pass oil pipe clip, applicable to both the Wraith III and Bentley III models. | 17th Sep 1938 | Box 8 \ 6 06-page41 | |
| Modifications for a reinforced and thickened combustion chamber on the Wraith III and Bentley 111 cylinder heads. | 19th Sep 1938 | Box 8 \ 6 06-page42 | |
| Experimental design for modified cylinder head cooling on the Wraith III. | 1st Oct 1938 | Box 8 \ 6 06-page43 | |
| Proposing a modification to the Wraith cylinder block for manufacturing efficiency. | 9th Oct 1938 | Box 8 \ 6 06-page44 | |
| Request for five Wraith cylinder heads for further testing and potential production use. | 14th Oct 1938 | Box 8 \ 6 06-page45 | |
| Modification to the coring of cylinder blocks for the Wraith model. | 21th Oct 1938 | Box 8 \ 6 06-page46 | |
| Modification to the coring of cylinder blocks for the Wraith model. | 28th Oct 1938 | Box 8 \ 6 06-page47 | |
| Cracking of Wraith cylinder blocks after heat treatment and analysis of the material. | 2nd Nov 1938 | Box 8 \ 6 06-page48 | |
| The fitting of a special cylinder block and new production Wraith pistons to unit EW.1923. | 5th Nov 1938 | Box 8 \ 6 06-page49 | |
| Requesting an updated drawing for the strengthened cylinder head on the Wraith & B.III models. | 8th Nov 1938 | Box 8 \ 6 06-page50 | |
| The impracticability of modifying Wraith rocker covers for cost reduction. | 2nd Mar 1939 | Box 8 \ 6 06-page51 | |
| The difficulty experienced when removing a Klingerit cylinder head gasket from a Wraith engine due to adhesion. | 15th Mar 1939 | Box 8 \ 6 06-page52 | |
| Proposed alteration to the cylinder head for the Wraith III and Bentley III models to improve valve seat cooling. | 11th May 1939 | Box 8 \ 6 06-page53 | |
| Factory costs for a Wraith cylinder liner. | 9th Jun 1939 | Box 8 \ 6 06-page54 | |
| New scheme for the Wraith II chassis front end, focusing on cost reduction and simplified assembly. | 25th Jan 1936 | Box 8 \ 7 07-page01 | |
| New design scheme for the Wraith II chassis rear end, focusing on the petrol tank and shock dampers. | 25th Jan 1936 | Box 8 \ 7 07-page02 | |
| Design for attaching the front suspension to the main chassis frame for the Wraith II model. | 4th Apr 1936 | Box 8 \ 7 07-page03 | |
| Design changes for the Wraith II front suspension to save weight and expense over the Phantom III design. | 29th May 1936 | Box 8 \ 7 07-page04 | |
| Proposed weight savings for the Wraith II suspension compared to the 25/30 HP model. | 30th Jun 1936 | Box 8 \ 7 07-page05 | |
| The design of the Wraith II front suspension yoke piece, comparing it to the Phantom III. | 30th Jun 1936 | Box 8 \ 7 07-page06 | |
| Expressing concern about high stress levels on the front suspension of the Wraith II model. | 9th Jun 1936 | Box 8 \ 7 07-page07 | |
| The design of the Wraith II front suspension lower triangle levers and yoke piece bearing. | 30th Jun 1936 | Box 8 \ 7 07-page08 | |
| Wraith II upper triangle levers for the front suspension. | 2nd Jul 1936 | Box 8 \ 7 07-page09 | |
| Letter from The Harboro' Rubber Co. Ltd arranging a meeting to discuss part No. FW.180. | 12th Sep 1936 | Box 8 \ 7 07-page10 | |
| Letter from The Harboro' Rubber Co. Ltd regarding the manufacture of softer rubber blocks for engine mountings. | 16th Sep 1936 | Box 8 \ 7 07-page11 | |
| Letter from The Harboro' Rubber Co. Ltd confirming a conversation about rubber blocks and the return of a mould. | 22th Sep 1936 | Box 8 \ 7 07-page12 | |
| Letter to The Harboro' Rubber Co. Ltd. regarding a mould for Part No. FW.180 and rubber-to-metal adhesion. | 23th Sep 1936 | Box 8 \ 7 07-page13 | |
| Transferring production of part FW.180 from Harboro Rubber Co. to British Tyre & Rubber Co. due to adhesion issues. | 23th Sep 1936 | Box 8 \ 7 07-page14 | |
| Request for comparative torque figures for the rubber rear engine mountings of the Wraith and 25/30 HP cars. | 12th Feb 1937 | Box 8 \ 7 07-page15 | |
| Modification to the Wraith III's high engine mounting for its torque snubbers. | 13th Mar 1937 | Box 8 \ 7 07-page16 | |
| Deflection test graph for a Wraith II gearbox rear support bracket. | 15th Mar 1937 | Box 8 \ 7 07-page17 | |
| Load-deflection graph for the Wraith II front engine mounting. | 12th Mar 1937 | Box 8 \ 7 07-page18 | |
| Alteration to the Wraith III high engine mounting by increasing the quantity of rubber. | 1st Apr 1937 | Box 8 \ 7 07-page19 | |
| Test results for the Wraith II gearbox support bracket 'Silent Bloc' bush. | 22th Aug 1937 | Box 8 \ 7 07-page20 | |
| Torsion test graph and diagram for a Wraith II gearbox rear support bracket. | 17th Feb 1937 | Box 8 \ 7 07-page21 | |
| Graph plotting torque against angular movement for a Wraith II gearbox rear support bracket mechanical assembly. | 22th Feb 1937 | Box 8 \ 7 07-page22 | |
| Graph showing torque versus angular movement for a 20/25 Gearbox Rear Suspension Bracket Leg. | 9th Mar 1937 | Box 8 \ 7 07-page23 | |
| Graph of torque vs angular movement and a diagram of a gearbox rear suspension bracket. | 10th Mar 1937 | Box 8 \ 7 07-page24 | |
| Alternative designs for the Wraith III high engine mounting. | 22th Apr 1937 | Box 8 \ 7 07-page25 | |
| Rubber silent bloc exhaust suspension for the Wraith model and requesting a similar system for a Bentley. | 13th May 1937 | Box 8 \ 7 07-page26 | |
| Design scheme for a rear engine mounting modification for the Wraith III 26-G-VI car. | 28th Jun 1937 | Box 8 \ 7 07-page27 | |
| Blueprints for a Wraith high engine mounting support bracket and associated parts. | 2nd Aug 1937 | Box 8 \ 7 07-page28 | |
| Modification to the nose bearing and torque arm for the Wraith III high engine mounting. | 3rd Aug 1937 | Box 8 \ 7 07-page29 | |
| Dispatch of front suspension parts and modifications for a Wraith. | 4th Aug 1937 | Box 8 \ 7 07-page30 | |
| Request for a drawing to fit 25 HP front engine mounting rubbers to a Wraith vehicle. | 18th Aug 1937 | Box 8 \ 7 07-page31 | |
| Request to produce 3 more sets of original front engine mounting parts for the Wraith. | 20th Aug 1937 | Box 8 \ 7 07-page32 | |
| Troubles with the rear engine mounting on the 25/30 HP model. | 22th Aug 1937 | Box 8 \ 7 07-page33 | |
| Blueprints and parts for the Wraith front engine mounting. | 23th Aug 1937 | Box 8 \ 7 07-page34 | |
| Requesting the build-up of an experimental raised engine mounting for the Wraith III for an endurance test. | 25th Aug 1937 | Box 8 \ 7 07-page35 | |
| The difficulties and alternative solutions for front engine mounting on a 25/30 HP vehicle. | 24th Aug 1937 | Box 8 \ 7 07-page36 | |
| Engine and exhaust system mountings for two Wraith III cars. | 26th Aug 1937 | Box 8 \ 7 07-page37 | |
| The design and testing of a new high front engine mounting for the Wraith III. | 26th Aug 1937 | Box 8 \ 7 07-page38 | |
| Requesting tests on the Phantom III to investigate the effect of engine mounting on sideways chassis shake, following a demonstration on a Wraith car. | 2nd Sep 1937 | Box 8 \ 7 07-page39 | |
| Request to prepare two schemes for the Wraith III engine mounting, focusing on torque absorption. | 7th Sep 1937 | Box 8 \ 7 07-page40 | |
| Parts and prints required for the Wraith front engine mounting. | 7th Sep 1937 | Box 8 \ 7 07-page41 | |
| Revised high front engine mounting for the Wraith III. | 9th Sep 1937 | Box 8 \ 7 07-page42 | |
| Requesting the preparation of two further sets of front engine mounting parts for the Wraith III. | 22th Sep 1937 | Box 8 \ 7 07-page43 | |
| Parts and blueprints for the Wraith front engine mounting and damper fixings. | 30th Sep 1937 | Box 8 \ 7 07-page44 | |
| New design for detachable rear engine support brackets for the Wraith III chassis. | 7th Oct 1937 | Box 8 \ 7 07-page45 | |
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