| Description | Date | Identifier | |
| Issues with drilled high-pressure valves on 20 HP rear shock absorbers. | 28th Mar 1929 | Box 55 \ 4 Scan332 | |
| Letter to Mr. Hancock suggesting drilling a hole in the high-pressure valve of 20 HP rear shock absorbers to reduce knocks. | 28th Mar 1929 | Box 55 \ 4 Scan333 | |
| Clarifying a misunderstanding regarding a high pressure test, stating it was for the 20 HP car, not the S.S. | 3rd Apr 1929 | Box 55 \ 4 Scan334 | |
| Confirming the drilling of high pressure valves for the SS rear hydraulic dampers. | 3rd Apr 1929 | Box 55 \ 4 Scan335 | |
| The design principles of shock dampers, covering leaks, valves, springs, and effective vibration control. | 1st Apr 1929 | Box 55 \ 4 Scan336 | |
| Handling issues with a 20 HP vehicle, specifically regarding dampers, springs, and a heavy Hooper body. | 6th Apr 1929 | Box 55 \ 4 Scan337 | |
| Modifications to the low and high pressure valves on 18-EX hydraulic dampers. | 6th Apr 1929 | Box 55 \ 4 Scan338 | |
| Instructions for altering valve loading and replacing washers on front hydraulic dampers and valves. | 6th Apr 1929 | Box 55 \ 4 Scan339 | |
| Instructions for modifying springs and dampers, including inserting packing pieces. | 8th Apr 1929 | Box 55 \ 4 Scan340 | |
| The effect of drilling holes in high-pressure valves for hydraulic dampers and testing different pressure loadings. | 8th Apr 1929 | Box 55 \ 4 Scan341 | |
| Instructions for altering damper loading using specified washers to improve low and high-speed ride. | 8th Apr 1929 | Box 55 \ 4 Scan342 | |
| Damper arrangements, steering shocks, and a report on a petrol gauge. | 9th Apr 1929 | Box 55 \ 4 Scan343 | |
| Design issue where a conduit obstructs access to the high-pressure valve on the 'SS' model's rear hydraulic shock absorbers. | 9th Apr 1929 | Box 55 \ 4 Scan344 | |
| Special spanner for removing a high-pressure valve cap on the rear dampers. | 9th Apr 1929 | Box 55 \ 4 Scan345 | |
| Letter discussing riding quality, the effect of drilled valves, and shock absorber settings. | 11th Apr 1929 | Box 55 \ 4 Scan346 | |
| Shock absorber valve settings and their effect on vehicle ride quality. | 11th Apr 1929 | Box 55 \ 4 Scan347 | |
| Letter discussing pressure-velocity instruments, shock absorber design, and road spring lubrication methods. | 22th Jun 1928 | Box 55 \ 4 Scan348 | |
| Graph plotting leakage rates for various shock absorber valve designs and part numbers. | 22th Jun 1928 | Box 55 \ 4 Scan349 | |
| Blueprint for a high pressure valve for a hydraulic shock absorber. | 10th Apr 1929 | Box 55 \ 4 Scan350 | |
| Drawing for a slotted high pressure valve for a hydraulic shock absorber. | 20th Jun 1928 | Box 55 \ 4 Scan351 | |
| Design and manufacturing tolerances for 'SS' rear hydraulic dampers to allow for load adjustment. | 12th Apr 1929 | Box 55 \ 4 Scan352 | |
| Specifications and recommendations for high and low pressure valve caps and damper springs. | 12th Apr 1929 | Box 55 \ 4 Scan353 | |
| Specifications for front damper springs, valve caps, and loads. | 12th Apr 1929 | Box 55 \ 4 Scan354 | |
| Blueprint detailing valve cap dimensions for S.S. Hydraulic Dampers. | 12th Apr 1929 | Box 55 \ 4 Scan355 | |
| Four graphs detailing the adjustment of S.S. damper loads for front and rear shock dampers. | 2nd Apr 1929 | Box 55 \ 4 Scan356 | |
| The cross steering tube fouling the front hydraulic dampers and a proposed solution to modify the tube's bend. | 2nd Apr 1929 | Box 55 \ 4 Scan357 | |
| From 'R' discussing improvements to hydraulic dampers based on road tests. | 4th Apr 1929 | Box 55 \ 4 Scan358 | |
| Design, issues, and improvements for hydraulic dampers. | 19th Apr 1929 | Box 55 \ 4 Scan359 | |
| Removal of dynamic restrictors from S.S. hydraulic spring dampers and subsequent production changes. | 22th Apr 1929 | Box 55 \ 4 Scan360 | |
| Letter requesting clarification on a report about hydraulic dampers and asking for a history of starter motor failures. | 29th Apr 1929 | Box 55 \ 4 Scan361 | |
| Test results and settings for S.S. hydraulic dampers and shock absorbers. | 29th Apr 1929 | Box 55 \ 4 Scan362 | |
| Steering and suspension tests, including pivot lean, damper settings, and buffer clearances. | 25th Apr 1929 | Box 55 \ 4 Scan363 | |
| Steering and tyre tests, detailing effects on ride quality, oscillations, and worn tyres. | 26th Apr 1929 | Box 55 \ 4 Scan364 | |
| Car riding quality, discussing issues with dampers, shocks, and steering performance. | 1st May 1929 | Box 55 \ 4 Scan365 | |
| Weakness of a bent rear shock damper bracket and the proposal to thicken it to double its strength. | 1st May 1929 | Box 55 \ 4 Scan366 | |
| Outlining conclusions and recommendations on the design and performance of hydraulic dampers. | 5th Mar 1929 | Box 55 \ 4 Scan367 | |
| Continued discussion on vehicle damping theory in relation to axle and body movement. | 1st May 1929 | Box 55 \ 4 Scan368 | |
| Request for details for tests on hydraulic shock absorbers. | 1st May 1929 | Box 55 \ 4 Scan369 | |
| Proposal for an automatically controlled shock damper system using an air spring, adjustable from the driver's seat. | 9th May 1929 | Box 55 \ 4 Scan370 | |
| Modifications to the casings of front and rear SS hydraulic dampers. | 14th May 1929 | Box 55 \ 4 Scan371 | |
| Experiments on riding quality, shock absorbers, and road holding, with a comparison to American conditions. | 14th May 1929 | Box 55 \ 4 Scan372 | |
| Suspension design and the effect of weight distribution on ride comfort for various car body types. | 14th May 1929 | Box 55 \ 4 Scan373 | |
| Improvements to vehicle riding comfort, focusing on road springs and shock absorber loading. | 14th May 1929 | Box 55 \ 4 Scan374 | |
| The results of shock absorber tests, comparing theoretical ideas with practical findings on load settings. | 14th May 1929 | Box 55 \ 4 Scan375 | |
| Achieving a soft ride using specific shock absorber loadings, referencing the Sales and Experimental Departments. | 20th Jun 1929 | Box 55 \ 4 Scan376 | |
| On the manufacturing difficulties of oil damper springs for valve F.80991/2. | 20th Jun 1929 | Box 55 \ 4 Scan377 | |
| Testing, rejection, and manufacturing specifications for shock absorber springs. | 22th Jun 1929 | Box 55 \ 4 Scan378 | |
| Test results for S.S. rear shock damper springs used on HP and L.P. valves. | 22th Jun 1929 | Box 55 \ 4 Scan379 | |
| Specifications for rear shock damper springs including high and low pressure values. | 3rd Jul 1929 | Box 55 \ 4 Scan380 | |
| Shock absorber knock complaints and modifications for 20 HP and 40/50 HP cars. | 3rd Jul 1929 | Box 55 \ 4 Scan381 | |
| Alterations to shock damper loads, including spring specifications and adjustment methods. | 15th Mar 1929 | Box 55 \ 4 Scan382 | |
| The new settings for a hydraulic shock absorber, detailing modifications to valve caps and springs. | 22th Aug 1929 | Box 55 \ 4 Scan383 | |
| Graphs and diagrams for front and rear hydraulic shock absorbers, detailing ball pin load versus adjusting washer thickness. | 17th Oct 1929 | Box 55 \ 4 Scan384 | |
| Requesting modifications to rear shock damper cover castings for hydraulic damper tests. | 17th Oct 1929 | Box 55 \ 4 Scan385 | |
| Recommendations regarding increased poundage on shock absorbers. | 5th Nov 1929 | Box 55 \ 4 Scan386 | |
| Communication regarding the adjustment of hydraulic dampers and how loads can be varied using different washers. | 21th Nov 1929 | Box 55 \ 4 Scan387 | |
| Shock absorber loads, discussing issues with hydraulic dampers and recommending a change in machining to a reamer finish. | 29th Nov 1929 | Box 55 \ 4 Scan388 | |
| Feedback on the performance of shock absorbers to inform a re-design. | 2nd Dec 1929 | Box 55 \ 4 Scan389 | |
| Investigating springing complaints and suspension issues for the Phantom I model. | 10th Dec 1929 | Box 55 \ 4 Scan390 | |
| Analysis of vehicle ride quality, discussing pitching, spring lubrication, hydraulic shock absorbers, and maximum spring deflection. | 10th Dec 1929 | Box 55 \ 4 Scan391 | |
| Experimental improvements to vehicle ride quality using different springs and drilled valves, focusing on Phantom I, Phantom II, and light fabric-bodied cars. | 10th Dec 1929 | Box 55 \ 4 Scan392 | |
| Specifying updated valve cap washer dimensions for Phantom II hydraulic shock dampers. | 10th Dec 1929 | Box 55 \ 4 Scan393 | |
| Frame torsional weakness in relation to shock absorbers, radiator 'jellying', and 'shimmy'. | 24th Feb 1930 | Box 55 \ 4 Scan394 | |
| Outlining recommendations for road springs and damping on Phantom II and 25 HP models. | 14th May 1930 | Box 55 \ 4 Scan395 | |
| List of urgent design work for cars, detailing potential improvements to the petrol pump, carburetter, gearbox, and shock dampers. | 20th May 1930 | Box 55 \ 4 Scan396 | |
| The philosophy of product design, continuous improvement, and remaining competitive. | 20th May 1930 | Box 55 \ 4 Scan397 | |
| Cover note for an attached document describing opinions on how to handle vehicle springing complaints from a service point of view. | 4th Jul 1930 | Box 55 \ 4 Scan398 | |
| Technical note discussing experiences and recommendations for car springing and damper settings. | 4th Jul 1930 | Box 55 \ 4 Scan399 | |
| Car suspension, focusing on the design and damping of cushions and squabs to improve ride comfort. | 4th Jul 1930 | Box 55 \ 4 Scan400 | |
| Suspension characteristics, specifically spring flexibility and shock absorber damping. | 3rd Oct 1930 | Box 55 \ 4 Scan401 | |
| Customer complaints for faulty hydraulic shock dampers, listing chassis numbers and the specific issues. | 3rd Oct 1930 | Box 55 \ 4 Scan402 | |
| Technical discussion on the evolving role and challenges of shock dampers in car design. | 15th Nov 1930 | Box 55 \ 4 Scan403 | |
| The development and performance of shock dampers and associated fittings. | 15th Nov 1930 | Box 55 \ 4 Scan404 | |
| Postscript discussing issues with shock dampers, their positioning, and problems with connecting rods and central oiling. | 18th Nov 1930 | Box 55 \ 4 Scan405 | |
| Modifications to a ball valve to address hydraulic shock absorber knocks. | 18th Nov 1930 | Box 55 \ 4 Scan406 | |
| Short memo regarding the dispatch of shock absorber diagrams after examination. | 1st Dec 1930 | Box 55 \ 4 Scan407 | |
| Letter to a Mr. Beaver explaining the historical design evolution of the Phantom 2's suspension and transmission systems. | 1st Dec 1930 | Box 55 \ 4 Scan408 | |
| Vehicle weight distribution, springing, and shock damper improvements on various models. | 1st Dec 1930 | Box 55 \ 4 Scan409 | |
| Letter from F. H. Royce discussing issues with shock dampers and comparing them to Lovejoy's design. | 1st Dec 1930 | Box 55 \ 4 Scan410 | |
| Performance and design issues of hydraulic dampers compared to competitor's, Lovejoy. | 1st Dec 1930 | Box 55 \ 4 Scan411 | |
| Design critique regarding the positioning of rear components under the frame and its impact on road clearance. | 2nd Dec 1930 | Box 55 \ 4 Scan412 | |
| The experience with hydraulic shock dampers on the Phantom I and Phantom II models. | 2nd Dec 1930 | Box 55 \ 4 Scan413 | |
| Analysis of shock damper issues, including noise, deflection, oil emulsification, and their effect on ride quality. | 2nd Dec 1931 | Box 55 \ 4 Scan414 | |
| Damper performance, high-speed road holding, and maintenance issues such as knocks and oil loss. | 2nd Dec 1930 | Box 55 \ 4 Scan415 | |
| The design and performance of various damper components, including pin joints, valves, and attachments. | 2nd Dec 1930 | Box 55 \ 4 Scan416 | |
| Report discussing damper springing, valve accessibility on Phantom II dampers, and effective mean ball pin load measurements. | 2nd Dec 1930 | Box 55 \ 4 Scan417 | |
| Diagrams showing the progressive falling off in rear damper efficiency with the reduction of stroke. | 2nd Dec 1930 | Box 55 \ 4 Scan418 | |
| Series of graphs showing the effect of restricting air vent ball lift on a Phantom II rear shock damper. | 21th Nov 1930 | Box 55 \ 4 Scan419 | |
| Graph and diagram illustrating S.S. rear shock damper lever tests. | 21th Nov 1930 | Box 55 \ 4 Scan420 | |
| Design and preference for double vertical piston type hydraulic dampers. | 15th Dec 1930 | Box 55 \ 4 Scan421 | |
| Design drawing with notes for a shock damper mechanism. | 24th Dec 1930 | Box 55 \ 4 Scan422 | |
| Print of a hydraulic shock damper with vertical pistons and a change to the filter design. | 24th Dec 1930 | Box 55 \ 4 Scan423 | |
| Negative effects of the vacuum feed system on engine performance and fuel consumption. | 24th Jul 1925 | Box 56 \ 1 Scan001 | |
| Investigations into vacuum feed, petrol economy, and fuel distribution issues on 40/50 and 20 HP models. | 8th Oct 1925 | Box 56 \ 1 Scan002 | |
| Vacuum feed performance on the 20 HP and New Phantom models, and suggesting carburetter improvements. | 11th Aug 1925 | Box 56 \ 1 Scan003 | |
| Potential causes of rich mixture in the vacuum feed tank and requesting data for a new design. | 11th Aug 1925 | Box 56 \ 1 Scan004 | |
| Standardisation of a special valve for the Autovac to improve slow running. | 22th Apr 1926 | Box 56 \ 1 Scan005 | |
| Preventing petrol starvation on 20-HP models by ensuring the petrol pipe slopes downwards correctly. | 4th Jun 1926 | Box 56 \ 1 Scan006 | |
| Petrol leaks from the 20-HP Autovac drain plug and suggesting the use of aluminium washers. | 16th Aug 1926 | Box 56 \ 1 Scan007 | |
| Tests on Autovacs with Aluminium heads instead of brass heads for 40/50 and 20/25 HP chassis, noting a price difference and potential savings. | 6th Jun 1930 | Box 56 \ 1 Scan008 | |
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