| Description | Date | Identifier | |
| 'booming' in Phantom II models, relating to sub-frame versus direct-on-frame body construction. | 27th Apr 1931 | Box 14 \ 8 Scan301 | |
| 'Jellying' issue, discussing the stiffening of vertical side members. | 28th Apr 1931 | Box 14 \ 8 Scan302 | |
| Confirming the dispatch and modification of a front dumb iron with a bumper pad. | 5th May 1931 | Box 14 \ 8 Scan303 | |
| Frame distortion tests measuring the effect of engine mounting on torsional frame stiffness and front end jellying. | 29th May 1931 | Box 14 \ 8 Scan304 | |
| Vehicle chassis jellying, damping, and engine mounting tests on various car models. | 29th May 1931 | Box 14 \ 8 Scan305 | |
| Series of five graphs comparing frame deflection angle against torque under various test conditions. | 28th May 1931 | Box 14 \ 8 Scan306 | |
| From the Print Room showing a date stamp. | 30th May 1931 | Box 14 \ 8 Scan307 | |
| Designs and testing procedures for deeper and stiffer chassis frames. | 4th Jul 1931 | Box 14 \ 8 Scan308 | |
| Arrangements to test three 40/50 cars without sub-frames. | 13th Jul 1931 | Box 14 \ 8 Scan309 | |
| Outlining five suggestions for producing and testing deeper frame side members for the P.2 model. | 13th Jul 1931 | Box 14 \ 8 Scan310 | |
| The trial of cars without subframes, detailing the positive results for the first car (31-GX) after 6,460 miles of continental use. | 10th Oct 1931 | Box 14 \ 8 Scan311 | |
| Removal of subframes for economy, referencing the report on 31-GX and Springfield's production. | 3rd Oct 1931 | Box 14 \ 8 Scan312 | |
| Record of a telephone conversation discussing balance weights, exhaust pipe failures, and frame fittings for Phantom II and 20/25 HP models. | 22th Oct 1931 | Box 14 \ 8 Scan313 | |
| Continued necessity of subframes due to a new engine mounting system. | 5th Nov 1931 | Box 14 \ 8 Scan314 | |
| Modified front and rear dumb irons for fitting bumpers to L.H. P.2 cars. | 10th Nov 1931 | Box 14 \ 8 Scan315 | |
| Experimental deeper side members and cross members for the Phantom II chassis. | 11th Nov 1931 | Box 14 \ 8 Scan316 | |
| Lack of experience with diamond mounting on car bodies not built on sub-frames for 40/50 and 20/25 models. | 16th Nov 1931 | Box 14 \ 8 Scan317 | |
| Improvements to the torsional stiffness of frames for larger cars. | 30th Nov 1931 | Box 14 \ 8 Scan318 | |
| Follow-up memo expressing concern over using diamond mounted engines on chassis with bodies that lack sub-frames. | 30th Nov 1931 | Box 14 \ 8 Scan319 | |
| Diamond engine mounting and frame stiffness on Phantom 1 and Phantom II cars. | 1st Dec 1931 | Box 14 \ 8 Scan320 | |
| The schemes for deeper side members for the Phantom II frame construction. | 8th Dec 1931 | Box 14 \ 8 Scan321 | |
| Urgent memo requesting the method for building a chassis with deeper side members. | 21th Dec 1931 | Box 14 \ 8 Scan322 | |
| Use of sub-frames on the 40/50 HP chassis, comparing rigidity and 'jellying' on two specific cars. | 19th May 1932 | Box 14 \ 8 Scan323 | |
| Requesting a decision on sub-frames for car bodies being ordered for the Paris and Olympia Shows. | 3rd Jun 1932 | Box 14 \ 8 Scan324 | |
| Urging an immediate decision on whether to build bodies with or without sub-frames for cars intended for the Paris Show. | 13th Jun 1932 | Box 14 \ 8 Scan325 | |
| The decision to cease using subframes in future car models and to inspect existing cars without them. | 17th Jun 1932 | Box 14 \ 8 Scan326 | |
| Recommending to hold up F.11 material, pending an agreement to delete subframes on future 40/50 hp cars. | 17th Jun 1932 | Box 14 \ 8 Scan327 | |
| Recommendation to omit a sub-frame and mentioning specific car examples. | 17th Jun 1932 | Box 14 \ 8 Scan328 | |
| Cause and a potential solution for chassis 'jellying' by using a sub-frame. | 6th Jul 1932 | Box 14 \ 8 Scan329 | |
| Decision on whether to use subframes for the 40/50 HP chassis for show cars versus customer cars. | 8th Jul 1932 | Box 14 \ 8 Scan330 | |
| Requesting a reply regarding the potential abandonment of subframes on the 40/50-HP chassis. | 15th Jul 1932 | Box 14 \ 8 Scan331 | |
| Decision to delete the body subframe on the Phantom II chassis. | 18th Jul 1932 | Box 14 \ 8 Scan332 | |
| Note on subframes and a standardisation sheet sent for agreement. | 18th Aug 1932 | Box 14 \ 8 Scan333 | |
| Discontinuation of body subframes and seeking a timeline for implementation on the 40/50-HP chassis. | 21th Jul 1932 | Box 14 \ 8 Scan334 | |
| The plan to delete body subframes for the O.2 series and questioning completion for the N.2 series. | 11th Aug 1932 | Box 14 \ 8 Scan335 | |
| The supply and potential deletion of body subframes for N.2 and O.2 series chassis. | 11th Aug 1932 | Box 14 \ 8 Scan336 | |
| Persistent issue of radiator wing movement and frame 'jellying' on the Phantom II model. | 18th Aug 1932 | Box 14 \ 8 Scan337 | |
| Tests conducted on mounting the radiator to the engine for the Phantom II. | 30th Aug 1932 | Box 14 \ 8 Scan338 | |
| Discontinuation of supplying body subframes due to economic and standardization reasons. | 30th Aug 1932 | Box 14 \ 8 Scan339 | |
| Inquiry regarding the discontinuation of fitting body subframes on the 40/50 chassis. | 12th Sep 1932 | Box 14 \ 8 Scan340 | |
| The replacement of body subframes with body brackets after chassis 118-MS. | 14th Sep 1932 | Box 14 \ 8 Scan341 | |
| Proposal for the deletion of the body sub-frame to reduce cost and weight. | 18th Jul 1932 | Box 14 \ 8 Scan342 | |
| Standardisation of chassis parts. | 15th Oct 1932 | Box 14 \ 8 Scan343 | |
| Request to drill the subframe girders to attach lead weights for testing frame jellying. | 25th Oct 1932 | Box 14 \ 8 Scan344 | |
| List of parts and modifications for the 3rd and 4th crossmembers on the Phantom II chassis to permit wells in the rear floor. | 28th Jul 1933 | Box 14 \ 8 Scan345 | |
| List of parts no longer required and instructions regarding modifications to the 3rd and 4th crossmembers. | 28th Jul 1933 | Box 14 \ 8 Scan346 | |
| Modifications to the frontal appearance of the Phantom II, specifically regarding a dropped front crossmember. | 5th Jan 1934 | Box 14 \ 8 Scan347 | |
| Expressing concern over proposed changes to the starting handle mechanism, which requires disconnecting the thermostat control. | 10th Jan 1934 | Box 14 \ 8 Scan348 | |
| From Sg. to E. with suggestions for camouflaging a radiator and shutters. | 10th Jan 1934 | Box 14 \ 8 Scan349 | |
| Modification to lower the stepirons by two inches on the 25 HP and P.2 models. | 14th Mar 1934 | Box 14 \ 8 Scan350 | |
| Standardisation of a concealed front cross member, headlamp mounting, and front apron. | 1st May 1934 | Box 14 \ 8 Scan351 | |
| Cost estimation for a parts standardisation modification on the 'S' series, including equipment and scrap values. | 15th May 1934 | Box 14 \ 8 Scan352 | |
| Standardisation of parts for creating wells in the rear floorboards to obtain lower seating. | 12th Jun 1934 | Box 14 \ 8 Scan353 | |
| Estimated cost for extra jigs, tools, and equipment for the 'S2' series. | 25th May 1934 | Box 14 \ 8 Scan354 | |
| Standardising the dropped front crossmember for the 25-HP and Bentley models. | 11th Jul 1934 | Box 14 \ 8 Scan355 | |
| Test results for Phantom II frame distortion under varying loads. | 18th Mar 1935 | Box 14 \ 8 Scan356 | |
| Description of a frame test setup with applied loads. | 18th Mar 1935 | Box 14 \ 8 Scan357 | |
| Modifications to the radiator suspension and cross member. | 3rd Nov 1925 | Box 15 \ 1 Scan001 | |
| Radiator with integral shutters and comparing it to the previous 'W' series. | 1st Nov 1925 | Box 15 \ 1 Scan002 | |
| Alternative radiator suspension design using spherical supports. | 7th Nov 1925 | Box 15 \ 1 Scan003 | |
| Front cross member and radiator suspension, referencing schematic N.sch.2103 and comparing it to EAC.8. | 12th Oct 1925 | Box 15 \ 1 Scan004 | |
| Status of experimental chassis 7-EX and 12-EX, concerning parts fitting and radiator standardisation. | 25th Aug 1926 | Box 15 \ 1 Scan005 | |
| Overheating tests in France, comparing fan and radiator positions on experimental cars 8-EX and 12-EX. | 1st Sep 1926 | Box 15 \ 1 Scan006 | |
| Cooling system performance of the 12-EX model and potential modifications. | 30th Sep 1925 | Box 15 \ 1 Scan007 | |
| Feedback and proposed alterations to the radiator design on the 12-EX model. | 1st Oct 1926 | Box 15 \ 1 Scan008 | |
| Confirming a conversation about Standardisation Sheet No.7250 and radiators with integral shutters. | 1st Dec 1926 | Box 15 \ 1 Scan009 | |
| Standardization of Phantom radiators with integral shutters. | 16th Dec 1926 | Box 15 \ 1 Scan010 | |
| Standardisation proposal for a thermometer with an electrical contact to warn drivers of boiling water. | 22th Sep 1926 | Box 15 \ 1 Scan011 | |
| Car appearance improvements related to radiators, bonnets, number plates, and frame height. | 22th Dec 1926 | Box 15 \ 1 Scan012 | |
| Controversy over radiator thickness, bonnet length, and the optimal diameter of radiator tubes. | 13th Jan 1927 | Box 15 \ 1 Scan013 | |
| Proposed design changes to a 40/50 bonnet and radiator. | 15th Jan 1927 | Box 15 \ 1 Scan014 | |
| Appearance of an integral radiator, enclosing prints and suggesting modifications to a sales model for approval. | 25th Jan 1927 | Box 15 \ 1 Scan015 | |
| Design modifications for radiators with integral shutters, including a table comparing the front radiator area of various car models. | 25th Jan 1927 | Box 15 \ 1 Scan016 | |
| Comparison of radiator designs focusing on tube dimensions and their effect on total cooling area and efficiency. | 28th Jan 1927 | Box 15 \ 1 Scan017 | |
| Dimensional corrections for the Phantom Radiator tank and filler size. | 28th Jan 1927 | Box 15 \ 1 Scan018 | |
| Revised radiator and bonnet design, suggesting the creation of a physical prototype. | 28th Jan 1927 | Box 15 \ 1 Scan019 | |
| Design modifications and alternative proposals for the Phantom radiator and bonnet. | 2nd Feb 1927 | Box 15 \ 1 Scan020 | |
| Proposed modifications to radiator and bonnet proportions, pending approval. | 5th Feb 1927 | Box 15 \ 1 Scan021 | |
| Improvements to the Phantom radiator and bonnet, focusing on integral shutters. | 10th Feb 1927 | Box 15 \ 1 Scan022 | |
| Modifications to bonnet fasteners, locks, and radiators for the 20 HP and 7-EX models. | 14th Feb 1927 | Box 15 \ 1 Scan023 | |
| Query regarding the unusually effective cooling of the EAC-8 (12-EX) engine and radiator following a trip to the Alps. | 14th Feb 1927 | Box 15 \ 1 Scan024 | |
| Difficulty of fitting a raised radiator and bonnet to car EAC.7 and proposing solutions. | 2nd Feb 1927 | Box 15 \ 1 Scan025 | |
| Feasibility of reducing radiator thickness for the Phantom EAC. 8 Type model. | 26th Feb 1927 | Box 15 \ 1 Scan026 | |
| Design specifications for a radiator with integral shutters for the 40/50HP Standard Phantom Chassis. | 9th Mar 1927 | Box 15 \ 1 Scan027 | |
| Design proposal for a 40/50 Phantom radiator with integral shutters, compared to a production version with separate shutters. | 8th Mar 1927 | Box 15 \ 1 Scan028 | |
| Faded document with a red 'Print Room' stamp from Derby. | 9th Mar 1927 | Box 15 \ 1 Scan029 | |
| Proposed modifications to the EAC. 8 radiator, discussing tube dimensions, cooling area, and bonnet height adjustments. | 17th Mar 1927 | Box 15 \ 1 Scan030 | |
| Status and filing of radiator drawing N.sch.2371. | 7th Apr 1927 | Box 15 \ 1 Scan031 | |
| Tests on fan positioning for improved cooling efficiency on the 12-EX and its proposed application to standard Phantom cars. | 25th Apr 1927 | Box 15 \ 1 Scan032 | |
| Change to narrower radiator tubes from 8mm to 7mm. | 11th Nov 1927 | Box 15 \ 1 Scan033 | |
| Alternative radiator suspension schemes for the 12-EX model, using a 'Ferobestos' bush type. | 22th Nov 1927 | Box 15 \ 1 Scan034 | |
| Design features and improvements for the EAC.7 vehicle, including the radiator and engine suspension. | 9th Jan 1928 | Box 15 \ 1 Scan035 | |
| Potential improvements to a vehicle's throttle cooling, induction, braking, and body design. | 4th Jul 1928 | Box 15 \ 1 Scan036 | |
| Technical review of the flexibility, stiffness and mounting of steering columns, scuttles, and dashboards for 20 HP and 40 HP models. | 4th Jul 1928 | Box 15 \ 1 Scan037 | |
| Modifications to the Phantom's radiator, bonnet, and dashboard for the G.2.B. series chassis. | 7th May 1928 | Box 15 \ 1 Scan038 | |
| Impact of a higher radiator on driver visibility for the Phantom model. | 8th May 1928 | Box 15 \ 1 Scan039 | |
| Proposals for a higher radiator, bonnet, and dash for the Phantom model. | 11th May 1928 | Box 15 \ 1 Scan040 | |
| Clarifying confusion over the 'E' steering position for the Phantom model, detailing a lower column design. | 11th May 1928 | Box 15 \ 1 Scan041 | |
| Rebuilding of chassis 15-EX with an ordinary long frame and proposed new components. | 16th May 1928 | Box 15 \ 1 Scan042 | |
| Parts for a Phantom Chassis experiment, specifically for an F-2-B Series. | 24th May 1928 | Box 15 \ 1 Scan043 | |
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