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).
Instructions for attention points on the J.S. Car concerning carburetion, ignition advance, and engine mounting.
| Identifier | ExFiles\Box 5\1\ 01-page141 | |
| Date | 1st March 1933 | |
| X6770 To H.{Arthur M. Hanbury - Head Complaints} Whyman from Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} Hs{Lord Ernest Hives - Chair}/Rml/BES1.3.33. J.S. Car We are handing this car over to you. The points which require attention are as follows:- CARBURATION We want to be able to demonstrate the best slow running consumptions, absence of 'luffing' up, that can be obtained with the existing combination of camshafts and induction pipe. The results should enable us to determine what fundamental modifications, if any, are required in the design. IGNITION ADVANCE We want to find out what is the correct ignition advance for this engine to give the maximum performance with the minimum detonation. The features which are at present wrong are:- (1) Compression ratio is too high being 6-1. We cannot fit another C & A gasket under the head because the push rods are too short to allow of this being done. We have therefore instructed another set of push rods, and when these are to hand the ignition tests should be carried out. (2) It is possible we have not the correct ignition advance characteristics. If we find that we cannot retard the ignition to prevent low speed detonation without impeding the high speed performance, we shall have to produce another automatic ignition advance curve. ENGINE MOUNTING When we have the carburetter and ignition into reasonable condition, we want to know what the car is like for torque re-action, and whether the engine mounting, generally, is sufficiently flexible to eliminate 'booms'. cont'd | ||