Rolls-Royce Archives
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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).
Comparing engine specifications and discussing design considerations for a V8 engine.

Identifier  ExFiles\Box 173\4\  img067
Date  20th November 1935 guessed
  
was removed by torsional flexibility in the flywheel. A crank damper is fitted at the front end. The production engine with no ordinary flywheel and no damper are rough but the engine with a cosmic flywheel is the smoothest I have ever met. Had no periods, either full throttle or running up the engine light up to 5000 rpm.

The crankshaft has 3 bearings of 2 1/2" dia. The rear 1 11/16" long, intermediate 1 3/16", and the front 1 11/16". The pins are 2 1/2" dia. The webs 1/2" wide. Side by siding with .006 total end float.

If we are forced to make a V8 engine I suggest trying one of these engines & laying it on the chassis on a 20/25". It would probably show high compression ratios (about 6.5") without any pickup roughness.

Some interesting figures All at 3600 rpm

Engine, port size, C/R, Comp: Pressure, Type
Buick 40, 3 1/8, 5.8, 115°, OHV
La{L. A. Archer} Salle, 4 3/8, 6.25, 133°, Sidevalve
V12, 4, 6.0, 135°, OHV
Chevrolet, 4, 5.6, 126, OHV
Pontiac, 3 7/8, 6.2, 148, Sidevalve

All the OHV engines had about the same volumetric efficiency of 80 at low speeds and 68 high speeds and the side valve engines 77 low speeds and 62 high speeds.
  
  


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