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).
Test data sheet showing induction pipe depression and necessary piston lift under various engine configurations at 3000 rpm.
| Identifier | ExFiles\Box 13\4\ 04-page116 | |
| Date | 28th February 1933 | |
| -2- Hs{Lord Ernest Hives - Chair}/Swdl.{Len H. Swindell}2/KT.28.2.33. All tests taken at 3000 r.p.m. (Open exhaust). Condition of test (Intake body-E.83324-only). | Induction Pipe depn. Ins. Hg. --- | --- Standard 2.25 dia. throttle body (std. 2.375 dia Valve). | 2.4 " " " " (Air Valve removed) | 2.1 Increased 2.375 dia. throttle body (std. 2.375 Valve ) | 2.3 " " " " (2.50 valve port ) | 2.3 " " " " (air valve removed ) | 2.0 Ø " " " " " Ø | Intake body removed otherwise as above test Ø | 1.9 NECESSARY PISTON LIFT .650 ins. Condition under which tested | Lift ins. | Depn. Ins. Hg. --- | --- | --- Standard 2.25 dia. throttle body. | .7 | 2.4 Standard 2.375 dia. valve port. | .6 | 2.4 Intake body only attached to carb. | .5 | 2.55 Open exhaust & 3000 r.p.m. | .4 | 2.8 | ||