| Description | Date | Identifier | |
| Blueprint of a six-cylinder engine component, possibly a gasket. | 23th Apr 1936 | Box 103 \ 4 scan0165 | |
| 25/30 HP engine water temperature tests, identifying poor circulation and proposing corrections. | 23th Apr 1936 | Box 103 \ 4 scan0166 | |
| Page 2 of a memo discussing a modification to reduce water loss and plans for further investigation on Bentley and Phantom III cars. | 23th Apr 1936 | Box 103 \ 4 scan0167 | |
| Radiator tests at Brooklands for Chassis No. 22-G-V. | 31th Mar 1936 | Box 103 \ 4 scan0168 | |
| Radiator tests data showing water temperatures and radiator shutter positions under various conditions. | 31th Mar 1936 | Box 103 \ 4 scan0169 | |
| Test report detailing engine and radiator water temperature readings under various conditions, including with a spring fitted and removed. | 31th Mar 1936 | Box 103 \ 4 scan0170 | |
| Engine cooling performance, mentioning local boiling and the effects of a spring and shutters. | 7th May 1936 | Box 103 \ 4 scan0171 | |
| Request to fit lengthened exhaust valve guides to cylinders 2 & 5 of a 25/30 HP unit for a test on valve temperatures. | 7th May 1936 | Box 103 \ 4 scan0172 | |
| Suggesting a modification to block waterways in the cylinder head rather than the cylinder for 25/30 and Bentley models. | 2nd Jul 1936 | Box 103 \ 4 scan0173 | |
| Modification of water flow by deleting water holes between the cylinder block and head for a more even temperature rise. | 23th Jun 1936 | Box 103 \ 4 scan0174 | |
| Cost estimate for extra jigs, tools, and equipment, and a note on bringing the 'L.2' series chassis into production. | 17th Jun 1936 | Box 103 \ 4 scan0175 | |
| Comparing valve diameters in Graham type cylinder heads versus the standard 25/30 unit. | 12th Aug 1936 | Box 103 \ 4 scan0176 | |
| Requesting the performance results of a deturbulated (Non-turbulent) head fitted to a 22-G-V engine. | 12th Oct 1936 | Box 103 \ 4 scan0177 | |
| Performance and potential standardisation of a 25/30 HP deturbulated cylinder head. | 13th Oct 1936 | Box 103 \ 4 scan0178 | |
| Follow-up communication regarding a complaint about a 25/30 HP engine running backwards after being switched off. | 30th Oct 1936 | Box 103 \ 4 scan0179 | |
| Comparative tests on the 25/30 deturbulated cylinder head and its planned standardisation. | 4th Nov 1936 | Box 103 \ 4 scan0180 | |
| Performance comparison between a standard and a deturbulated cylinder head for the 25/30 model. | 5th Nov 1936 | Box 103 \ 4 scan0181 | |
| Graph of ignition governor curves for a 25/30 deturbulated head. | 16th May 1936 | Box 103 \ 4 scan0182 | |
| Test report on a four-port cylinder head for car 32-EX, detailing water loss and temperature differences. | 5th Nov 1936 | Box 103 \ 4 scan0183 | |
| Comparing the performance of a deturbulated cylinder head against other designs for the 25/30 HP engine. | 9th Nov 1936 | Box 103 \ 4 scan0184 | |
| Four-port cylinder head experiment for the 25/30 HP engine. | 12th Nov 1936 | Box 103 \ 4 scan0185 | |
| Modifications to the cylinder head LeC.5222 for the 25/30 HP engine. | 3rd Dec 1936 | Box 103 \ 4 scan0186 | |
| Standardisation of parts for a 25/30 HP deturbulated cylinder head to give a smoother engine. | 19th Dec 1936 | Box 103 \ 4 scan0187 | |
| Note on the production viability and tooling costs for the 'P2' series chassis. | 30th Dec 1936 | Box 103 \ 4 scan0188 | |
| Listing the design changes required for fitting a 25/30 4-port cylinder head. | 30th Dec 1936 | Box 103 \ 4 scan0189 | |
| Transfer of a cylinder block and pistons from chassis GTL-34 for investigation. | 4th Jan 1937 | Box 103 \ 4 scan0190 | |
| Request to supply a modified 30 HP cylinder head and other parts for consumption tests on car GAE 20, Unit No. 18. | 15th Feb 1937 | Box 103 \ 4 scan0191 | |
| Investigation into a 25/30 HP cylinder head with preignition trouble caused by an accumulation of rusted cast iron chips. | 16th Feb 1938 | Box 103 \ 4 scan0192 | |
| Pre-ignition trouble in a 25/30 HP cylinder head caused by accumulated iron chips. | 22th Feb 1937 | Box 103 \ 4 scan0193 | |
| Crankcase depression tests comparing pressure and extractor breather methods to manage oil vapour. | 24th Feb 1937 | Box 103 \ 4 scan0194 | |
| Graph from crankcase depression tests, plotting depression in inches of water against speed in M.P.H. | 23th Feb 1937 | Box 103 \ 4 scan0195 | |
| Cylinder block wear, the use of Chromidium iron, and Brinell hardness for 25/30 & Bentley models. | 29th May 1937 | Box 103 \ 4 scan0196 | |
| Brinell hardness of cylinder iron, wear measurements, and comparative costs leading to a standardisation proposal. | 29th May 1937 | Box 103 \ 4 scan0197 | |
| Comparison of cylinder bore wear rates per 1000 miles for various engines. | 31th May 1937 | Box 103 \ 4 scan0198 | |
| Comparison of cylinder wear rates for different units after testing in France. | 31th May 1937 | Box 103 \ 4 scan0199 | |
| Describing the 'Goshawk II' rear spare wheel carrier arrangement, referencing drawing No. lec.1369. | 30th Mar 1921 | Box 103 \ 5 scan0001 | |
| Further details for the Goshawk 11, specifically about fitting a temporary petrol level indicator. | 9th Apr 1921 | Box 103 \ 5 scan0002 | |
| Relocation of the rear cross member and spare wheel on the Goshawk II model. | 5th May 1921 | Box 103 \ 5 scan0003 | |
| Design of a spare wheel carrier, comparing it to an American 'Essex' car. | 5th May 1921 | Box 103 \ 5 scan0004 | |
| Query regarding wheel clearance for a 'Goshawk 11' model with various hood types, and a handwritten update on the decided wheel size. | 5th May 1921 | Box 103 \ 5 scan0005 | |
| The proposed new position of the spare wheel on the 'Goshawk II' car. | 6th May 1921 | Box 103 \ 5 scan0006 | |
| Confirming the satisfactory new position of the spare wheel carrier at the rear of the car. | 1st May 1921 | Box 103 \ 5 scan0007 | |
| Revisions to the 'Goshawk II' spare wheel carrier, petrol tank, petrol filler, and filler cap. | 9th Jul 1921 | Box 103 \ 5 scan0008 | |
| Extract regarding the design of the wheel carrier. | 8th Oct 1921 | Box 103 \ 5 scan0009 | |
| The standardization of accessories for the Goshawk 11 chassis. | 30th Dec 1921 | Box 103 \ 5 scan0010 | |
| Decision memo regarding the design of a spare wheel carrier. | 30th Dec 1921 | Box 103 \ 5 scan0011 | |
| Tail-light and number plate arrangement for the Goshawk 11. | 14th Feb 1922 | Box 103 \ 5 scan0012 | |
| The fitting of luggage grids and tyre carriers to three Goshawks for a 10,000-mile trial. | 22th Feb 1922 | Box 103 \ 5 scan0013 | |
| Revised design for the Goshawk wheel carrier on the running board, requesting a prototype and a price. | 1st Oct 1922 | Box 103 \ 5 scan0014 | |
| Suggested modification to the Goshawk wheel carrier to suit coachbuilding. | 1st Nov 1922 | Box 103 \ 5 scan0015 | |
| Modification of a wheel carrier design and who should deal with it. | 6th Nov 1922 | Box 103 \ 5 scan0016 | |
| Note about a request from Sales to cover the exposed hub of the Goshawk spare wheel with a sheet metal plate. | 12th May 1922 | Box 103 \ 5 scan0017 | |
| Official order for fifty sets of side spare wheel carriers for 20 HP chassis, with a design query about a concealing hub plate. | 23th Dec 1922 | Box 103 \ 5 scan0018 | |
| Order for 50 Goshawk spare wheel carriers and the requirement for a standardisation sheet before fitting. | 27th Dec 1922 | Box 103 \ 5 scan0019 | |
| Proposed cover for the Goshawk 11 side spare wheel carrier hub. | 30th Dec 1922 | Box 103 \ 5 scan0020 | |
| On issues with the 20 HP chassis spare wheel carrier for the side position, recommending a return to an earlier design. | 8th Jan 1923 | Box 103 \ 5 scan0021 | |
| Problems with the side-mounted spare wheel carrier on the 20 HP chassis and proposing alternative solutions. | 10th Jan 1923 | Box 103 \ 5 scan0022 | |
| The release of parts and design change for the Goshawk side-mounted spare wheel carrier. | 29th Jan 1923 | Box 103 \ 5 scan0023 | |
| Goshawk standardisation sheet for a side position spare wheel carrier. | 5th Feb 1923 | Box 103 \ 5 scan0024 | |
| Goshawk spare wheel fitting that unscrews itself while driving. | 6th Feb 1923 | Box 103 \ 5 scan0025 | |
| Investigating an issue with the Goshawk spare wheel fitting working loose. | 1st Feb 1923 | Box 103 \ 5 scan0026 | |
| Returning a standardisation sheet with costs for a 20 HP chassis spare wheel carrier. | 8th Feb 1923 | Box 103 \ 5 scan0027 | |
| Standardisation report for a spare wheel carrier for side position. | 30th Jan 1923 | Box 103 \ 5 scan0028 | |
| Standardisation of a spare wheel carrier for side position. | 30th Jan 1923 | Box 103 \ 5 scan0029 | |
| Issues with Goshawk spare wheels coming loose. | 9th Feb 1923 | Box 103 \ 5 scan0030 | |
| Fault where the spare wheel carrier bolt on 20 HP cars works loose, recommending an immediate fix. | 2nd Feb 1923 | Box 103 \ 5 scan0031 | |
| Proposal to add a lock to the spare wheel bolt for the 20 HP Goshawk due to issues with it working loose. | 3rd Mar 1923 | Box 103 \ 5 scan0032 | |
| Two experimental suggestions for locking the Goshawk 11 wheel carrier set screw. | 14th Mar 1923 | Box 103 \ 5 scan0033 | |
| The failure of the 20 HP spare wheel bracket. | 16th Mar 1923 | Box 103 \ 5 scan0034 | |
| Inquiry into the failure of a 20 HP spare wheel bracket. | 16th Mar 1923 | Box 103 \ 5 scan0035 | |
| Alternative positive lock for the Goshawk 11 wheel carrier set screw. | 16th Mar 1923 | Box 103 \ 5 scan0036 | |
| Broken 20 HP spare wheel bracket, likely due to defective brazing. | 19th Mar 1923 | Box 103 \ 5 scan0037 | |
| Failure of a 20HP spare wheel bracket due to faulty brazing. | 29th Mar 1923 | Box 103 \ 5 scan0038 | |
| Mr. Royce's feedback on a heavy, electro-plated spare wheel carrier dust cover and requesting a new version made from black-enamelled sheet aluminium. | 20th Jun 1923 | Box 103 \ 5 scan0039 | |
| Design and reinforcement of spare wheel carriers for 20HP, 40/50HP and Goshawk models. | 23th Nov 1923 | Box 103 \ 5 scan0040 | |
| Extract from a sales visit discussing the placement of the 20 HP spare wheel. | 8th Feb 1924 | Box 103 \ 5 scan0041 | |
| Extract from a sales visit report concerning a side wheel carrier scratching paintwork, with a proposed modification. | 12th Feb 1924 | Box 103 \ 5 scan0042 | |
| Weak wheel carrier for the 20 HP model and a proposal to investigate strengthening it. | 14th Jul 1924 | Box 103 \ 5 scan0043 | |
| Mr. Royce's preferred method for a lock on the 20 HP chassis spare wheel bolt. | 4th Sep 1924 | Box 103 \ 5 scan0044 | |
| Adjustments for spare wheel carriers on the 20-HP chassis following the standardization of new heavy-duty tyres. | 7th Jun 1926 | Box 103 \ 5 scan0045 | |
| Design issues and improvements for spare wheel carriers, luggage carriers, and step irons on Phantom & Goshawk models. | 3rd Mar 1927 | Box 103 \ 5 scan0046 | |
| Riding qualities and the fitting of a rear luggage box and spare wheel carrier for Phantom & 20 HP models. | 29th Apr 1927 | Box 103 \ 5 scan0047 | |
| Special parts for the Rear Spare Wheel Carrier and Luggage Grid on a 20 HP Chassis. | 5th Aug 1927 | Box 103 \ 5 scan0048 | |
| Parts required for a Side Spare Wheel Carrier on a 20 HP Chassis. | 3rd Aug 1927 | Box 103 \ 5 scan0049 | |
| Proposing a handle-operated central bolt for 20 HP wheel carriers, referencing models X.5600 and X.8600. | 7th Sep 1927 | Box 103 \ 5 scan0050 | |
| Parts and modifications for a side spare wheel carrier on a 20-HP chassis. | 22th Sep 1927 | Box 103 \ 5 scan0051 | |
| Inquiry regarding the status of operating the central bolt on 20 HP wheel carriers without a spanner. | 11th Oct 1927 | Box 103 \ 5 scan0052 | |
| The standardization of a central bolt for a 20 HP spare wheel carrier. | 12th Oct 1927 | Box 103 \ 5 scan0053 | |
| Requesting feedback on a modified 20 HP spare wheel carrier for potential use on the Phantom model. | 13th Oct 1927 | Box 103 \ 5 scan0054 | |
| The standardisation of a bolt for the 20 HP spare wheel carrier handle. | 19th Oct 1927 | Box 103 \ 5 scan0055 | |
| Finalized design for a Phantom spare wheel carrier, its variations, and interchangeability. | 20th Oct 1927 | Box 103 \ 5 scan0056 | |
| Proposed change from a hexagon to a handle on the 20HP spare wheel carrier. | 4th Nov 1927 | Box 103 \ 5 scan0057 | |
| Proposal to standardize the spare wheel fixing bolt with a handle instead of a hexagon head. | 7th Nov 1927 | Box 103 \ 5 scan0058 | |
| Form detailing information for fitting a new part to a chassis, including costs and test dates. | 19th Mar 1928 | Box 103 \ 5 scan0059 | |
| Design modifications for the rear end of 'India 3 & 4' models, covering the frame, petrol tank, wheel carrier, tail lamp, and exhaust. | 22th May 1928 | Box 103 \ 5 scan0060 | |
| Modifications to the 20 HP rear wheel carrier for larger low-pressure tyres. | 4th Jul 1928 | Box 103 \ 5 scan0061 | |
| Breakage of tubes on 20 HP side spare wheel carriers and suggesting a design improvement. | 8th Sep 1928 | Box 103 \ 5 scan0062 | |
| Proposed new rear wheel carriers for the 20 HP model. | 17th Oct 1928 | Box 103 \ 5 scan0063 | |
| Alternative rear end arrangements, including wheel carriers and luggage grids. | 31th Oct 1928 | Box 103 \ 5 scan0064 | |
| Proposed system for carrying two spare wheels at the rear using a triangular bracket. | 14th Nov 1928 | Box 103 \ 5 scan0065 | |
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