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).
The effects of setting exhaust tappet at various clearances on cylinder pressure.
| Identifier | WestWitteringFiles\K\September1923\ Scan61 | |
| Date | 17th August 1928 guessed | |
| LIGHT SPRING CARD - G.11. FIRING. EXHAUST TAPPET SET AT VARIOUS CLEARANCES. This demonstrates two points :- (a) The bump can be produced apart from back pressure by making the last portion of the opening of the exhaust valve ineffective. (b) The nature of the bump has a distinct affect on the point at which the cylinder commences to fill up, for in this case the opening of the inlet valve is the same each time, but the larger the positive pressure when the inlet valve opens, the later does the charge start getting in as one would expect. Positive pressure in cylinder when Inlet Valve opens. No clearance = 3.72 lbs. per sq. in. .015 " = 8.05 " " " .050 " = 15.5 " " " --------------------------------- | ||