From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Proposal for testing the Aspin valve for reliability and antidetonating qualities on a Bentley engine.
| Identifier | ExFiles\Box 134\1\ scan0239 | |
| Date | 1st May 1940 | |
| - 5 - Cont'd.{John DeLooze - Company Secretary} to make it at least square, if not a larger bore than stroke, since this will improve the breathing, the combustion chamber remains compact and there are no limitations due to inertia of the valve gear. PROPOSAL FOR TESTING ASPIN VALVE. Initially it would appear to be desirable to test the Aspin valve and head for : (a) reliability. (b) antidetonating qualities. on a multi-cylinder engine, since all single cylinder tests are suspect when applied to monoblock main units. Fortunately, we have a complete 4 1/2 litre Bentley with an overhead camshaft drive which might have been designed to test the Aspin valve and head, which is at present doing nothing. Our proposal is to get Aspin to design and produce a head for this unit as soon as possible and then run off the necessary proof tests. The Bentley unit can be fitted with parts that will enable it to run reliably with 1- lbs sq. inc. boost which should be sufficient to get some indication as to the way the valve will function under "Merlin" conditions. If the merits of the valve can be substantiated, it's application to 4- stroke and 2-stroke aviation engines might be considered. SUMMARY. The Aspin valve has a number of potential advantages which appear to justify a preliminary test. This test can be carried out on an in-line mono-block liquid cooled 6-cylinder engine 3 1/2 x 4 1/2, which already exists with the necessary overhead camshaft drive. AHS. | ||