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).
Proposals for the engine stroke, crankshaft, and other components for the Peregrine and Bensport models.
| Identifier | ExFiles\Box 3\4\ 04-page076 | |
| Date | 13th July 1932 | |
| X4553 To Sg.{Arthur F. Sidgreaves - MD} Wor.{Arthur Wormald - General Works Manager}} from E.{Mr Elliott - Chief Engineer} c. Hs.{Lord Ernest Hives - Chair} By.{R.W. Bailey - Chief Engineer} PN.{Mr Northey} E.4HP.13.7.32. I.4027 X.4553 re Peregrine and Bensport. We had some conversation with R.{Sir Henry Royce} this afternoon, during which he discussed the question of what stroke should be used on Peregrine and Bensport. He agrees that it is desirable to avoid altering Peregrine where possible, and is willing to leave the stroke 4.125" unaltered, but he wants it to be the same for Bensport, and still stipulates that the crankshaft and other parts shall be interchangeable for both engines. We put before R.{Sir Henry Royce} certain proposals with regard to the crankshaft and balance weights whereby we hope to raise the major critical of the crankshaft of 4.125 stroke to somewhere approaching 6000 r.p.m. which we consider would render both Peregrine and Bensport safe for operation up to 5000 r.p.m. Bensport cannot safely be allowed to exceed this speed on account of the Powerplus blower. Subject to certain tests, the results of which we can already supply, R.{Sir Henry Royce} is agreeable to these modifications. In these proposals we still retain our present size crankpin which enables the connecting rod to pass through the bore, and leaves the present Peregrine engine unaltered except for the modification to the main bearings, which we have already arranged to do. We also put before R.{Sir Henry Royce} our proposals with regard to making a Peregrine carburetter of the latest R.R. expanding type, but with certain simplifications, arrived at by deleting the mixture control, and he has quite readily agreed to these proposals. Regarding the other part of Peregrine, R.{Sir Henry Royce} does not think the gearbox scaled down from J.B. sufficiently robust and his intention is to use the Bensport gearbox fitted with right-hand change. | ||