Rolls-Royce Archives
         « Prev  Box Series  Next »        

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).
Ignition advance governor design challenges, including a graph and tests on alternative piston materials.

Identifier  ExFiles\Box 48\2\  Scan426
Date  1st February 1926 guessed
  
contd :-
-3-

[Text from graph]
GRAPH I
IGNITION ADVANCE DEGREES
ENGINE R.P.M.
DELAYED LOW SPEED ADVANCE WITH GOVERNOR WTS BEING HELD DOWN WITH SMALL INNER PISTON (ON LATER CONVENTIONAL WTS - STONE COLD)
2-3° INITIAL ADVANCE
STANDARD AND 75 X
LIMIT OF ADVANCE FOR MAX POWER
[Stamped text on graph]
MADE AT CREWE

[Main body text]
The reason we were unable to reduce the advance at high speeds was because the governor design did not allow us to fit control springs of the necessary rating. We have the strongest springs we can fit with a safe stress. The only alternative was to reduce the governor weights. We considered that this was undesirable because with the present weights the small inner piston does not commence to lift until 700 r.p.m. We have, however, been carrying out tests with reduced governor weights and a small inner piston of reduced weight. Previously we have not used aluminum for this item because it shewed a greater tendency to stick than brass in the presence of grit. We are now sending this item for a 10,000 miles test in duralumin.

The relay that ...
  
  


Copyright Sustain 2025, All Rights Reserved.    whatever is rightly done, however humble, is noble
An unhandled error has occurred. Reload 🗙