Rolls-Royce Archives
         « Prev  Box Series  Next »        

Specifications for machining a Large Bore Bentley cylinder head to achieve a 6.4/1 compression ratio.


Identifier  ExFiles\Box 86\1\  scan0178
Date  14th November 1935
  
To By. {R.W. Bailey - Chief Engineer}

X219

Hs {Lord Ernest Hives - Chair} /Smth.24/KW.14.11.35.

Large Bore Bentley.

When the head Ex.18392 is machined to give 6.4/1 C.R. (119 c.c. capacity), the depth of the combustion chamber from the ceiling to the joint face is 1.150". We have obtained this figure by direct measurement.

This is using a .050" gasket and with the crown of the piston .030" from the top face of the block at T.D.C.

Hs {Lord Ernest Hives - Chair} /Smth.
  
  
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).


Copyright Sustain 2026, All Rights Reserved.    whatever is rightly done, however humble, is noble
An unhandled error has occurred. Reload 🗙