| Description | Date | Identifier | |
| Required modification for petrol tanks with outside fillers on two specific cars to resolve fuel leakage from the breather pipe union. | 14th Mar 1934 | Box 17 \ 5 Scan221 | |
| Standardisation report for a bottom washer for valve springs. | 24th Sep 1926 | Box 17 \ 6 Scan001 | |
| Standardisation of solid key type bottom tappets to produce a more consistent quiet tappet. | 24th Sep 1926 | Box 17 \ 6 Scan002 | |
| Note on a standardisation sheet regarding the cost analysis of replacing old tappets. | 5th Oct 1926 | Box 17 \ 6 Scan003 | |
| Cost implications of standardizing tappets. | 5th Oct 1926 | Box 17 \ 6 Scan004 | |
| Test report on 'turbulent' type heads for the lighter Phantom engine, aimed at reducing detonation and continued firing. | 10th Dec 1926 | Box 17 \ 6 Scan005 | |
| Report page discussing engine test results, comparing an original head to an alternative, focusing on detonation and turbulence. | 10th Dec 1926 | Box 17 \ 6 Scan006 | |
| Engine head performance detailing compression ratio tests and ignition characteristics. | 10th Dec 1926 | Box 17 \ 6 Scan007 | |
| Engine timing, detonation, and self-ignition characteristics of a turbulent type cylinder head. | 10th Dec 1926 | Box 17 \ 6 Scan008 | |
| Engine experiments concerning self-ignition, turbulence, and the effects of using smaller valves. | 10th Dec 1926 | Box 17 \ 6 Scan009 | |
| Summary of test results on the Lighter Phantom engine, comparing different head and valve configurations. | 10th Dec 1926 | Box 17 \ 6 Scan010 | |
| Preparations for road and bench testing three different engine heads with a specific compression ratio. | 10th Dec 1926 | Box 17 \ 6 Scan011 | |
| Graph of Ignition Advance versus B.M.E.P. curves for different Aluminium Phantom engine configurations at 1000 RPM. | 11th Dec 1928 | Box 17 \ 6 Scan012 | |
| Blank document reverse with a Print Room stamp. | 11th Dec 1928 | Box 17 \ 6 Scan013 | |
| Graph of ignition advance curves for various Phantom engine configurations against engine RPM. | 2nd Dec 1926 | Box 17 \ 6 Scan014 | |
| Power comparison graph for an Aluminium Phantom engine with different valve sizes. | 2nd Dec 1926 | Box 17 \ 6 Scan015 | |
| Graph of Ignition Advance versus B.M.E.P. curves for an Aluminium Phantom engine at 1000 RPM. | 27th Oct 1916 | Box 17 \ 6 Scan016 | |
| Drawing of smaller diameter inlet and exhaust valves for the Lighter Phantom Engine. | 27th Oct 1916 | Box 17 \ 6 Scan017 | |
| The reverse side of a document showing a date stamp from Derby and a handwritten number. | 11th Dec 1926 | Box 17 \ 6 Scan018 | |
| Valve gear rocker geometry for the RAC.10, Phantom and 20 HP models to reduce noise when seating. | 3rd Mar 1928 | Box 17 \ 6 Scan019 | |
| Modified rocker angle for the sports Phantom, including a diagram illustrating eccentric thrust. | 1st Feb 1928 | Box 17 \ 6 Scan020 | |
| Query regarding modifications made to Phantom valve springs due to insufficient coil clearance. | 1st Feb 1928 | Box 17 \ 6 Scan021 | |
| Cylinder head blueprint, focusing on valve layout, rockers, and gear adjustments. | 22th Feb 1928 | Box 17 \ 6 Scan022 | |
| Query regarding the purpose of a small screw introduced on the 20 HP valve gear. | 23th Feb 1928 | Box 17 \ 6 Scan023 | |
| EAC.10 valve gear, suggesting duralumin for the rocker bar supports and noting thermal expansion effects. | 2nd Feb 1928 | Box 17 \ 6 Scan024 | |
| The EAC.10 valve gear, comparing rocker shaft dimensions and estimating shaft deflection under load. | 27th Feb 1928 | Box 17 \ 6 Scan025 | |
| EAC.10 & India 3 valve sizes, enclosing another document. | 6th Mar 1928 | Box 17 \ 6 Scan026 | |
| And comparing engine valve sizes for various models. | 6th Mar 1928 | Box 17 \ 6 Scan027 | |
| Valve noise issues in a 15EX engine and proposed actions for resolution. | 7th Mar 1926 | Box 17 \ 6 Scan028 | |
| Two different valve gear rocker geometries to minimise scrub and valve noise, referencing a trial on a Phantom engine. | 7th Mar 1926 | Box 17 \ 6 Scan029 | |
| Making the exhaust and inlet valve guides interchangeable for the Phantom Aluminium Head. | 23th Mar 1928 | Box 17 \ 6 Scan030 | |
| 'R.' concerning the satisfactory state of the SS. Engine Valve Gear. | 4th Apr 1928 | Box 17 \ 6 Scan031 | |
| Valve stretching on a Phantom model, comparing different steel compositions and proposing a strengthened valve design. | 25th Apr 1928 | Box 17 \ 6 Scan032 | |
| Continued memorandum discussing materials and shock loads on car and aero engine valve stems. | 26th Apr 1928 | Box 17 \ 6 Scan033 | |
| Modifications to Phantom valves, specifically increasing the stem diameter for inlet valves. | 26th Apr 1928 | Box 17 \ 6 Scan034 | |
| Phantom valve stretching, proposing to scrap valve steel with high silicon and switch to a heavier exhaust valve design. | 7th May 1928 | Box 17 \ 6 Scan035 | |
| Valve gear design, clearances, and proposed modifications for Phantom & EAC.10 engines. | 7th May 1928 | Box 17 \ 6 Scan036 | |
| Continuation page of a memorandum proposing modifications to feeler gauges, plug settings, and cam designs for the Phantom model. | 9th May 1928 | Box 17 \ 6 Scan037 | |
| Technical memo discussing the design and specifications for valve lift curves and associated cam components. | 9th May 1928 | Box 17 \ 6 Scan038 | |
| Valve spring performance and noise issues on Phantom engines with turbulent heads. | 1st May 1928 | Box 17 \ 6 Scan039 | |
| Technical memorandum discussing the performance and characteristics of Phantom double valve springs. | 11th May 1928 | Box 17 \ 6 Scan040 | |
| Investigating a high-pitched clicking noise from the valve gear at 1250 r.p.m. on experimental cars. | 19th May 1928 | Box 17 \ 6 Scan041 | |
| Reminder to supply figures for tappet clearance variations on Phantom engines. | 19th May 1928 | Box 17 \ 6 Scan042 | |
| Required co-efficient of expansion for Phantom push rods based on nickel content. | 22th May 1928 | Box 17 \ 6 Scan043 | |
| Ignition timing setting for the turbulent head. | 31th May 1928 | Box 17 \ 6 Scan044 | |
| Method to test various valve steels on an engine test bed. | 11th Jun 1928 | Box 17 \ 6 Scan045 | |
| Final recommendations for the valve and ignition timing of an aluminium head engine. | 14th Jun 1928 | Box 17 \ 6 Scan046 | |
| Two cases of broken valve springs on F.2.B. Chassis engines. | 28th Jun 1928 | Box 17 \ 6 Scan047 | |
| Calculation of E.A.C.10 valve lift curves and cam forms for Condor and Falcon engines. | 29th Jun 1928 | Box 17 \ 6 Scan048 | |
| Case of a valve spring breaking during a Unit Test. | 9th Jul 1928 | Box 17 \ 6 Scan049 | |
| Test report on Phantom Push Rods, concluding that a new oiling method offers no advantage. | 10th Jul 1928 | Box 17 \ 6 Scan050 | |
| Design change to the valve gear cams, increasing their width for improved wear and lubrication. | 25th Jul 1928 | Box 17 \ 6 Scan051 | |
| On the stretching of exhaust valves, identifying insufficient tappet clearance as the cause. | 1st Nov 1928 | Box 17 \ 6 Scan052 | |
| Depot sheet detailing the tappet adjustment procedure for Phantom F.2.B. series engines and onwards. | 1st Nov 1928 | Box 17 \ 6 Scan053 | |
| Telegram from Royce to Hives requesting a call regarding valve gear noise. | 7th Nov 1928 | Box 17 \ 6 Scan054 | |
| Suggestion to increase the coil clearance on SS valve springs by altering the bottom washer. | 8th Nov 1928 | Box 17 \ 6 Scan055 | |
| Tappet pad wear in the S.S. engine after 50 hours of testing and a proposed solution. | 9th Nov 1928 | Box 17 \ 6 Scan056 | |
| New taper valve springs and camshaft provisions to increase engine speed for the 20 HP model. | 10th Nov 1928 | Box 17 \ 6 Scan057 | |
| Sending a Tappet to Mr. Royce for examination. | 10th Nov 1928 | Box 17 \ 6 Scan058 | |
| Telegram from Royce regarding required modifications to tappet springs. | 12th Oct 1928 | Box 17 \ 6 Scan059 | |
| Relaying a telegram from Royce with instructions for modifying tappet springs. | 12th Nov 1928 | Box 17 \ 6 Scan060 | |
| Design and development strategy for the 'SS' chassis, including rollerless tappets and spring pressure. | 2nd Nov 1928 | Box 17 \ 6 Scan061 | |
| Engine valve train components, including cam and follower hardness, lubrication, and spring pressure. | 13th Nov 1928 | Box 17 \ 6 Scan062 | |
| Proposed modifications for the 'SS' valve gear lubrication system. | 13th Nov 1928 | Box 17 \ 6 Scan063 | |
| 'SS' valve springs, proposing the use of standard Phantom springs with modifications. | 13th Nov 1928 | Box 17 \ 6 Scan064 | |
| Trial of nitrifying hardening on 'SS' and aero engine components. | 19th Nov 1928 | Box 17 \ 6 Scan065 | |
| The material required to produce rollerless tappets for the SS engine. | 20th Nov 1928 | Box 17 \ 6 Scan066 | |
| Installation and potential modification of the 'SS' rear axle damper for easier valve access. | 21th Nov 1928 | Box 17 \ 6 Scan067 | |
| Query on selectively hardening parts during the nitriding process, suggesting copper-plating as a method. | 22th Nov 1928 | Box 17 \ 6 Scan068 | |
| Recommendation to alter the thread count on the 'SS' tappet adjusting screw for finer adjustment. | 28th Nov 1928 | Box 17 \ 6 Scan069 | |
| The required feeler gauge blade sizes for the SS unit. | 8th Dec 1928 | Box 17 \ 6 Scan070 | |
| Querying the correct tappet clearance for SS models with new cam forms. | 11th Dec 1928 | Box 17 \ 6 Scan071 | |
| Experiments and findings related to 'SS' valve rocker lubrication systems, particularly concerning cold starts. | 22th Jan 1929 | Box 17 \ 6 Scan072 | |
| Modifications to an engine's oil supply system to prevent exhaust smoke. | 26th Jan 1929 | Box 17 \ 6 Scan073 | |
| Proposed method for locating the 'SS' valve tappet guide. | 26th Jan 1929 | Box 17 \ 6 Scan074 | |
| Investigation into a suggestion to offset the tappet instead of the camshaft for 'SS' valve gear and left-handed engines. | 1st Feb 1929 | Box 17 \ 6 Scan075 | |
| Tappet mechanism design, including taper pins, tappet guides, and camshaft lubrication. | 2nd Feb 1929 | Box 17 \ 6 Scan076 | |
| Sending drawings for 'SS' valve cover, inlet cam form, and valve gear. | 2nd Feb 1929 | Box 17 \ 6 Scan077 | |
| Potential design modifications for the SS. Valve Gear and Desaxe Tappets. | 2nd Feb 1929 | Box 17 \ 6 Scan078 | |
| Simplification of the chassis engine valve rocker cover design. | 6th Feb 1929 | Box 17 \ 6 Scan079 | |
| Various schemes and proposals for valve rocker lubrication. | 6th Feb 1929 | Box 17 \ 6 Scan080 | |
| Continued note on an experiment to allow blow-off oil to lubricate the camshaft and tappet mechanism. | 1st Feb 1929 | Box 17 \ 6 Scan081 | |
| Schemes for improving the lubrication of the 'SS' valve gear. | 1st Feb 1929 | Box 17 \ 6 Scan082 | |
| Two schemes for valve rocker lubrication on the 'SS' engine. | 2nd Feb 1929 | Box 17 \ 6 Scan083 | |
| Update on the accuracy of jigging dowel pins for the valve tappet guide location. | 12th Feb 1929 | Box 17 \ 6 Scan084 | |
| Request for the various oil pressure figures (high, intermediate, low) when starting the 'SS' model from cold. | 15th Feb 1929 | Box 17 \ 6 Scan085 | |
| Design suggestions and material choices for a valve cover. | 16th Feb 1929 | Box 17 \ 6 Scan086 | |
| Design and testing of an SS engine valve rocker cover. | 21th Feb 1929 | Box 17 \ 6 Scan087 | |
| Comparing valve gear lubrication oil pressures during engine warm-up versus normal running conditions. | 1st Feb 1929 | Box 17 \ 6 Scan088 | |
| Note on the maximum oil pressures for the 'SS' engine when starting from cold. | 19th Feb 1929 | Box 17 \ 6 Scan089 | |
| Technical memorandum discussing the design of an SS valve gear cover, including features, noise transmission, and structural stiffening options. | 25th Feb 1929 | Box 17 \ 6 Scan090 | |
| Alloy used in German castings and a modification to a stud and thumb nut arrangement. | 29th Feb 1928 | Box 17 \ 6 Scan091 | |
| Telegram requesting particulars of a tappet spring used on the S S 10000 miles car. | 29th Feb 1928 | Box 17 \ 6 Scan092 | |
| The S.S. valve tappet guide location and set screw arrangement. | 14th Feb 1929 | Box 17 \ 6 Scan093 | |
| Agreeing to test a suggested lubrication method for the 'SS' Valve Gear. | 2nd Mar 1929 | Box 17 \ 6 Scan094 | |
| Design, materials, and manufacturing of an SS. Valve Cover, suggesting the use of magnesium. | 1st Mar 1929 | Box 17 \ 6 Scan095 | |
| Design, testing, and potential improvements of an 'SS' taper valve spring. | 14th Mar 1929 | Box 17 \ 6 Scan096 | |
| Agreeing to test tapered valve springs against parallel ones for superiority regarding periodic vibrations. | 25th Mar 1929 | Box 17 \ 6 Scan097 | |
| The testing of SS valve springs, noting a difficulty with natural frequencies. | 23th Apr 1929 | Box 17 \ 6 Scan098 | |
| Improvements to Phantom valve springs to prevent valve bounce at high speeds. | 10th Jun 1929 | Box 17 \ 6 Scan099 | |
| | | | |
