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).
Performance comparison graph for long and extra long reach plugs on a Peregrine engine.
| Identifier | ExFiles\Box 1\8\ B001_X100 Engine Chassis-page195 | |
| Date | 29th June 1932 guessed | |
| COMPARISON OF LONG AND EXTRA LONG REACH PLUGS ON PEREGRINE RM.{William Robotham - Chief Engineer}PR9. LONG REACH PLUGS .680 REACH EXTRA " " .950 REACH 5.85" R OPEN EX. SINGLE 1 5/8 THROTTLE DIA: S.U. VALVES DIA: AND LIFT AS ON RM.{William Robotham - Chief Engineer}PR5. INLETS .004 EX .006 B.H.P. R.P.M. B.M.E.P. 17 IN 31 Ex 40 .020 CLCE 105.5° CAMSHAFT REACH .950 REACH .680 | ||