| Description | Date | Identifier | |
| Graph comparing the top water temperature of experimental setups 18 E.X. and 19 E.X. against miles run. | 25th Jun 1930 | Box 12 \ 7 07-page091 | |
| Blueprint detailing a modification to a front undershield to improve the cooling system. | 26th Jun 1930 | Box 12 \ 7 07-page092 | |
| Tests of completed cars, specifically concerning issues with the P.2 bonnet material being too soft and bending, with a suggested improvement for the stiffeners. | 26th Jun 1930 | Box 12 \ 7 07-page093 | |
| Scheme for a concealed bonnet side hinge for the P.2. and 25 HP models. | 28th Jun 1930 | Box 12 \ 7 07-page094 | |
| Extract from a report on tests of completed cars regarding the difficulty of producing louvered bonnets from a harder material. | 5th Jul 1930 | Box 12 \ 7 07-page095 | |
| Second report on Brooklands radiator tests, detailing fuel supply and autovac performance. | 9th Jul 1930 | Box 12 \ 7 07-page096 | |
| Vehicle performance issues related to high temperatures and fuel supply, specifically concerning the vacuum pump. | 9th Jul 1930 | Box 12 \ 7 07-page097 | |
| Cooling system fan belt performance and fuel mixture strength issues at high speeds. | 9th Jul 1930 | Box 12 \ 7 07-page098 | |
| Tests concerning pre-ignition, fuel supply, and radiator design improvements. | 19th Jul 1930 | Box 12 \ 7 07-page099 | |
| Engine cooling circulation tests, analyzing water temperature under various conditions and speeds. | 9th Jul 1930 | Box 12 \ 7 07-page100 | |
| Report discussing car overheating issues, cooling system performance, and the effects of various driving conditions. | 9th Jul 1930 | Box 12 \ 7 07-page101 | |
| Recommendations for improvements to the fan belt, autovac, bonnet shutters, and cooling system, with proposed tests for the Phantom models. | 9th Jul 1930 | Box 12 \ 7 07-page102 | |
| Graphs showing the results of cooling system tests, examining the effect of fan configuration, speed, and ventilation. | 2nd Jul 1930 | Box 12 \ 7 07-page103 | |
| Graphs illustrating the effect of water circulation on engine overheating under various conditions. | 2nd Jul 1930 | Box 12 \ 7 07-page104 | |
| Graph of top and bottom water temperatures plotted against seven different engine cooling configurations during a Brooklands test. | 2nd Jul 1930 | Box 12 \ 7 07-page105 | |
| Graph showing the effect of temperature on complete car circulation. | 1st Jul 1930 | Box 12 \ 7 07-page106 | |
| Cooling tests for 25 HP and 40/50 HP models, focusing on radiator tube size and design. | 1st Jul 1930 | Box 12 \ 7 07-page107 | |
| The upcoming test of a square tube radiator and track comparisons with other cars. | 1st Jul 1930 | Box 12 \ 7 07-page108 | |
| Optimal size of radiator tubes for engine cooling and related effects on the carburetter. | 14th Jul 1930 | Box 12 \ 7 07-page109 | |
| Extract discussing issues with P.2 bonnets, including scuttle gap uniformity and louvred panel construction. | 15th Jul 1930 | Box 12 \ 7 07-page110 | |
| Requesting clarification on the type of bonnet ventilation fitted to car 24-EX in France. | 16th Jul 1930 | Box 12 \ 7 07-page111 | |
| Number of shutter ventilators on a car bonnet and the naming convention. | 18th Jul 1930 | Box 12 \ 7 07-page112 | |
| The approval and standardisation of an altered bonnet and dashboard for the Phantom II car. | 18th Jul 1930 | Box 12 \ 7 07-page113 | |
| Design of a 2nd L.H. P.2 model for the American market, focusing on the bonnet, instrument board, and front apron. | 21th Jul 1930 | Box 12 \ 7 07-page114 | |
| Alteration to the bonnet and dash for the 'N2' series chassis. | 22th Jul 1930 | Box 12 \ 7 07-page115 | |
| Approval and standardisation of components for the Second L.H. P.2 model for America. | 22th Jul 1930 | Box 12 \ 7 07-page116 | |
| Expediting an approved alteration to a bonnet and dash, which is for appearance rather than technical reasons. | 23th Jul 1930 | Box 12 \ 7 07-page117 | |
| Impracticality of bonnet shutters and suggesting an improved, more easily operated design. | 30th Jul 1930 | Box 12 \ 7 07-page118 | |
| Query regarding omitting side bonnet ventilators on a Left Hand Phantom Two. | 21th Aug 1930 | Box 12 \ 7 07-page119 | |
| Update on investigations concerning shutters in bonnets. | 25th Aug 1930 | Box 12 \ 7 07-page120 | |
| From C. to Hs. requesting an update on a matter following a cable from Oy. | 23th Aug 1930 | Box 12 \ 7 07-page121 | |
| Number and placement of shutters on Phantom bonnets for cooling. | 29th Aug 1930 | Box 12 \ 7 07-page122 | |
| Methods to mitigate radiator water loss on the Phantom II model. | 31th Aug 1930 | Box 12 \ 7 07-page123 | |
| Report discussing the design of square tube radiators and improvements to bonnet ventilation. | 31th Aug 1930 | Box 12 \ 7 07-page124 | |
| Poor quality of the current bonnet lock and vertical louvres, requesting new parts. | 31th Aug 1930 | Box 12 \ 7 07-page125 | |
| Brief typed acknowledgement regarding Phantom Bonnets. | 1st Sep 1930 | Box 12 \ 7 07-page126 | |
| Overheating issues with the Phantom II model and the efficiency of its bonnet cooling ventilators. | 1st Sep 1930 | Box 12 \ 7 07-page127 | |
| Technical explanation of the cooling system design and the reasons for potential overheating in a Phantom II. | 1st Sep 1930 | Box 12 \ 7 07-page128 | |
| Instructions regarding the instrument board warning lamp, cooling system boiling, and bonnet ventilation for hot climates. | 2nd Sep 1930 | Box 12 \ 7 07-page129 | |
| Instructions on the engine's red warning lamp behavior and running with the cut-out open on Continental roads. | 2nd Sep 1930 | Box 12 \ 7 07-page130 | |
| Retention of front and rear shutters for the Phantom II cooling system to address petrol heat issues. | 3rd Sep 1930 | Box 12 \ 7 07-page131 | |
| Deletion and painting process of bonnet shutters. | 9th Jul 1927 | Box 12 \ 7 07-page132 | |
| Confirming decisions on the design of 40/50 HP bonnets, specifically regarding shutters and louvres. | 22th Jul 1927 | Box 12 \ 7 07-page133 | |
| Effects of removing rear shutters on engine cooling efficiency. | 30th Jun 1927 | Box 12 \ 7 07-page134 | |
| Standardisation of chassis parts for an improved type of bonnet lock to overcome customer complaints. | 17th Dec 1929 | Box 12 \ 7 07-page135 | |
| Proposed and recent modifications to the vehicle's cooling system, including shutters, overflow valves, radiators and louvres. | 1st Oct 1930 | Box 12 \ 7 07-page136 | |
| Instruction memo to stop the 25HP flywheel and clutch job and modify the bonnet louvres. | 11th Oct 1930 | Box 12 \ 7 07-page137 | |
| New louvred bonnet design, scheme 3153, with horizontal louvres. | 11th Oct 1930 | Box 12 \ 7 07-page138 | |
| Request for a progress update on three experiments concerning pedal stems and bonnet designs. | 11th Oct 1930 | Box 12 \ 7 07-page139 | |
| Status update on experiments concerning adjustable pedal stems, concealed bonnet hinges, and Phantom II bonnet modifications. | 13th Oct 1930 | Box 12 \ 7 07-page140 | |
| Design improvements for radiators, bonnets, overflow valves, and bonnet vents. | 14th Oct 1930 | Box 12 \ 7 07-page141 | |
| Proposed modification to the bonnet to improve the body line for a continuous look. | 16th Oct 1930 | Box 12 \ 7 07-page142 | |
| Criticisms and potential improvements for bonnets and radiators. | 25th Oct 1930 | Box 12 \ 7 07-page143 | |
| Design suggestions for a filler cap, horizontal louvres, and bonnet sides. | 25th Oct 1930 | Box 12 \ 7 07-page144 | |
| Radiator tubes, bonnet vents and shutter design styles. | 27th Oct 1930 | Box 12 \ 7 07-page145 | |
| Modifying bonnet fasteners for the Phantom II model to prevent lifting on bad roads. | 27th Oct 1930 | Box 12 \ 7 07-page146 | |
| Design and performance of radiators and bonnets, comparing square tubes to round tubes. | 30th Oct 1930 | Box 12 \ 7 07-page147 | |
| Instructing a new, stronger spring for the 40/50 HP chassis bonnet catch. | 5th Dec 1930 | Box 12 \ 7 07-page148 | |
| The preparation of two different bonnet types, one welded steel and one riveted aluminium, for the 25-EX car. | 10th Jan 1931 | Box 12 \ 7 07-page149 | |
| Inquiring about the status of updating to modern bonnet ventilators. | 4th Feb 1931 | Box 12 \ 7 07-page150 | |
| Implementation of a 100% stronger spring for the Phantom bonnet catches to eliminate rattles. | 4th Feb 1931 | Box 12 \ 7 07-page151 | |
| The development of new bonnet ventilators for the Phantom II model. | 5th Feb 1931 | Box 12 \ 7 07-page152 | |
| Chasing the progress on designs for the 40/50 - Phantom II model's Bonnet Ventilation. | 10th Feb 1931 | Box 12 \ 7 07-page153 | |
| Accompanying a rough sketch of a bridge piece for a car bonnet to prevent damage. | 11th Feb 1931 | Box 12 \ 7 07-page154 | |
| Standardisation of chassis parts including a shallow tank radiator, wider dashboard and overlapping bonnet. | 24th Jul 1930 | Box 12 \ 7 07-page155 | |
| Standardisation of chassis parts to revert to four ventilating panels in the bonnet to reduce overheating. | 10th Jul 1930 | Box 12 \ 7 07-page156 | |
| Design assumptions, material specifications, and construction methods for new car bonnets. | 19th Feb 1931 | Box 12 \ 7 07-page157 | |
| Prints and originals for bonnet ventilators. | 3rd Mar 1931 | Box 12 \ 7 07-page158 | |
| Requesting a set of new ventilated bonnet shutters for cooling tests on car 19-EX at Brooklands. | 13th Apr 1931 | Box 12 \ 7 07-page159 | |
| Standardisation of a revised bonnet with concealed hinges overhanging the dash. | 13th Jan 1931 | Box 12 \ 7 07-page160 | |
| Form detailing particulars for a chassis alteration, including the first chassis number and associated costs. | 27th Apr 1931 | Box 12 \ 7 07-page161 | |
| Fitting stronger springs (E.61914) to the bonnet clips on Phantom II models. | 28th May 1931 | Box 12 \ 7 07-page162 | |
| Tests carried out to ascertain and eliminate bonnet movement and knocks by testing different radiator and engine mountings. | 18th Jun 1931 | Box 12 \ 7 07-page163 | |
| Diagram showing bonnet movement measurements in thousandths of an inch under chassis twist conditions. | 11th Jun 1931 | Box 12 \ 7 07-page164 | |
| Bonnet panel clearance on 40/50 & 25 HP models to prevent knocking from frame twisting. | 11th Jun 1931 | Box 12 \ 7 07-page165 | |
| Design and manufacturing of rivetless bonnets, comparing steel and aluminium options. | 18th Jun 1931 | Box 12 \ 7 07-page166 | |
| The design and material considerations for aluminium bonnets, including hinges and rivets. | 18th Jun 1931 | Box 12 \ 7 07-page167 | |
| The standardisation and modification of P.2 bonnets. | 20th Jun 1931 | Box 12 \ 7 07-page168 | |
| Design and construction of a rivetless aluminium bonnet for the 20/25 model. | 1st Jun 1931 | Box 12 \ 7 07-page169 | |
| The supply of drop-sided bonnets in relation to spare wheel placement on various chassis models. | 24th Jun 1931 | Box 12 \ 7 07-page170 | |
| Design, operation, and construction of flip-flap bonnet shutters for the P.2 model. | 26th Jun 1931 | Box 12 \ 7 07-page171 | |
| Bonnet riveting and material choice, specifically steel flaps in aluminium panels and rust prevention. | 26th Jun 1931 | Box 12 \ 7 07-page172 | |
| Criticisms and required modifications for flip-flop type bonnet ventilators. | 26th Jun 1931 | Box 12 \ 7 07-page173 | |
| Bonnet rattle and temperature tests, with notes on steering and petrol boiling issues. | 29th Jun 1931 | Box 12 \ 7 07-page174 | |
| Design and material choice for a rivetless bonnet, comparing a proposed design with one from Armstrong-Siddeley. | 4th Jul 1931 | Box 12 \ 7 07-page175 | |
| Alteration to the Phantom II bonnet side plates to avoid a gap with the chassis. | 6th Jul 1931 | Box 12 \ 7 07-page176 | |
| Design and material choice for car bonnets, comparing aluminium and steel options. | 7th Aug 1931 | Box 12 \ 7 07-page177 | |
| Design proposal for a steel bonnet without rivets, showing sections of the top and side hinges. | 8th Jul 1931 | Box 12 \ 7 07-page178 | |
| Technical report on the investigation and resolution of bonnet knocking issues on the 25-EX model. | 8th Jul 1931 | Box 12 \ 7 07-page179 | |
| Agreeing to a bonnet design and clarifying modifications for the coachbuilder. | 13th Jul 1931 | Box 12 \ 7 07-page180 | |
| Standardisation sheet discussing the alteration to the pivot point of flip flap type bonnet ventilators. | 14th Jul 1931 | Box 12 \ 7 07-page181 | |
| Alternative designs for rivetless bonnets, comparing aluminium against steel. | 15th Jul 1931 | Box 12 \ 7 07-page182 | |
| Design and production of rivet-less aluminium car bonnets and associated issues with louvres. | 20th Aug 1931 | Box 12 \ 7 07-page183 | |
| Achieving the interchangeability of bonnets for L.H. and N.2 series R.H. cars. | 1st Sep 1931 | Box 12 \ 7 07-page184 | |
| Phantom II cooling tests, covering radiator air temperature rise and bonnet ventilation. | 17th Sep 1931 | Box 12 \ 7 07-page185 | |
| Graph showing the rise of air temperature through a radiator matrix versus road speed at two different engine water temperatures. | 16th Sep 1931 | Box 12 \ 7 07-page186 | |
| Set of graphs comparing air pressure under a plain bonnet versus a louvered bonnet at different road speeds and gears. | 16th Sep 1931 | Box 12 \ 7 07-page187 | |
| P.2 Cooling tests comparing air pressure under bonnets fitted with flip-flap shutters versus a louvred bonnet. | 19th Sep 1931 | Box 12 \ 7 07-page188 | |
| Graphs showing air pressure under the bonnet versus road speed for a Chassis 20 EX under various conditions. | 18th Sep 1931 | Box 12 \ 7 07-page189 | |
| Bonnet fitting issues related to packings and recommending their removal from future production. | 30th Sep 1931 | Box 12 \ 7 07-page190 | |
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