Issues with pistons, gasket leakage, and boost levels for the supercharged 'Bensport' engine.
| Identifier | ExFiles\Box 86\2\ scan0001 | |
| Date | 20th September 1932 | |
| X236 E. {Mr Elliott - Chief Engineer} from Hs {Lord Ernest Hives - Chair} /Rn. {Mr Robinson} c. to By. {R.W. Bailey - Chief Engineer} Hs {Lord Ernest Hives - Chair} /Rn. {Mr Robinson} 7/KT. 20.9.32. PISTONS FOR SUPERCHARGED BENSPORT(Codename for 3 1/2-litre Bentley). At the present moment we have no pistons that will give us less than 5.85 : 1 c.r. on Peregrine(Experimental Bentley car never produced / Aero Engine), and actually with the metal gasket, 6.1 : 1. We think that we should have pistons giving 5.25 and 5 : 1 c.r. for Bensport(Codename for 3 1/2-litre Bentley). Until we get these pistons we do not think that we can usefully run a larger size of blower, as at present the engine has about reached its limit with the large amount of boost we are giving it, and the cylinder studs have shewn themselves to be inadequate, by leakage from the gasket, as you have seen yourself. At 3000 r.p.m. this leakage is alarming. It seems problematic whether the slightly larger studs will cure the trouble. We are positive that we shall eventually have trouble with the higher boost, but if we can get the 5.25 c.r. pistons, we will run a test which will represent what is proposed for Bensport(Codename for 3 1/2-litre Bentley), and will enable us to make a decision on the cylinder attaching facilities. Hs {Lord Ernest Hives - Chair} /Rn. {Mr Robinson} | ||
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).