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).
Requesting modifications to a 20 HP engine to achieve variable compression ratios for testing.
| Identifier | ExFiles\Box 105\2\ scan0208 | |
| Date | 18th March 1930 | |
| To RHC.{R. H. Coverley - Production Engineer} From Hs{Lord Ernest Hives - Chair}/Rn.{Mr Robinson} c. to CHP. 85040 Hs{Lord Ernest Hives - Chair}/Rn.{Mr Robinson} 2/MJ.18.3.30. 20 HP. UNIT. We want to arrange a variable compression 20 HP. engine between the limits of 5.25 and 6 - 1. Will you please put through a set of 6 - 1 pistons to E.55576, the necessary modification being adding .155 to the crown. We propose to get the intermediate compression ratios by putting aluminium distance pieces under the cyl. block. Will you please make three such washers in the gauges specified, if these are not available the thickness we should like the pieces machined to are .025, .050, .100. We do not expect to run above 5.75 - 1 which will mean that the cylinder block will be raised .100. The existing tappet adjustment will accommodate this and we do not consider it necessary to have new cylinder studs. Packing washers will be needed for the water pump and controls but these can be rigged up on the test bed. Will you please fit the pistons and packing washer .050 thick to engine unit Cos.C.1. now in the test house. We also require an up to date exhaust manifold on this unit. Hs{Lord Ernest Hives - Chair}/Rn.{Mr Robinson} | ||