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).
Letter from English Racing Automobiles Ltd providing crankshaft and connecting rod dimensions and discussing design details.
| Identifier | ExFiles\Box 115\3\ scan0030 | |
| Date | 10th August 1937 | |
| ENGLISH RACING AUTOMOBILES LTD E R A BOURNE LINCS TELEPHONE BOURNE 121 DIRECTORS H.W.COOK RAYMOND MAYS PETER BERTHON Handwritten notes: Filed, Miss answer, 1020 OUR REF. AB/EP.{G. Eric Platford - Chief Quality Engineer} DATE 10th August 1937. Messrs. Rolls Royce, Ltd., Experimental Department, Derby. MANUFACTURERS OF "E.R.A." RACING CARS MURRAY JAMIESON SUPERCHARGERS AUTOMOBILE RESEARCH ENGINEERS CUSTOMERS' CARS ARE DRIVEN BY OUR STAFF ONLY AT CUSTOMERS' OWN RISK Dear Sirs, In reply to your request by telephone this afternoon we have pleasure in supplying the undermentioned particulars. Diameter of crankpin. 2 1/8" -.001"/-.002". Bore of Connecting rod. 58 m/m.{Mr Moon / Mr Moore} +.02/-.01 Diameter of crankshaft centre Journal. 4 1/8" -.0007"/-.0015". Diameter of crankshaft bearing housing. 4 3/8" +.001/+.0005. We understand that you do not approve of locating the connecting rod shells by the bolts and in this connection we would welcome your views on and objections to this layout. It is not impossible to incorporate shims in our design and if necessary we would modify our connecting rod to enable them to be fitted. We are not, however, able to increase the bolt centres and grooves will in any case have to be provided in the shells to clear the bolts. Concerning the finish machining operation we feel confident that this could be carried out here, and we would be prepared to handle it. We would however appreciate details of what is entailed and particulars of the tools needed. Yours faithfully, ENGLISH RACING AUTOMOBILES LTD. [Signature] Barratt DESIGNS DEPT. AND AT BROOKLANDS TRACK, WEYBRIDGE, SURREY | ||