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).
Comparison of Powerplus and Roots Alfa-Romeo supercharger efficiencies.
| Identifier | ExFiles\Box 124\5\ scan0088 | |
| Date | 21th June 1932 | |
| RIG TESTS OF CAR SUPERCHARGERS. COMPARISON OF "POWERPLUS" & ROOTS. ALFA-ROMEO EFFICIENCIES. Top Graph: EFFICIENCY % RPM POWERPLUS 1570 CC. ALFA-ROMEO 1420 CC. TEST 21-6-32 BAR. 31.10 AIR TEMP. 17°C DRY AIR (FIGURES ARE INCHES Hg. PRESS R) 1.625" S.U. CARB. ON INTAKE ADIABATIC EFFICIENCIES CURVE LABELS: 10", 20", 30" Bottom Graph: EFFICIENCY % RPM (FIGURES ARE INCHES Hg. PRESS R) TEST 21-6-32 BAR. 31.10 AIR TEMP. 17°C DRY AIR POWERPLUS 1570 CC. ALFA-ROMEO 1420 CC. VOLUMETRIC EFFICIENCIES 1.625" S.U. CARB. ON INTAKE CURVE LABELS: 10", 20", 30" F.J.A. / 4732 | ||