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).
Comparative performance and oil temperature test report for two vehicles at Brooklands.
| Identifier | ExFiles\Box 108\2\ scan0234 | |
| Date | 25th April 1939 | |
| 600, 600c & 1320 1st. page only, sent out To By.{R.W. Bailey - Chief Engineer} c. to Sg.{Arthur F. Sidgreaves - MD} c. to Hs.{Lord Ernest Hives - Chair} c. to Da.{Bernard Day - Chassis Design} c. to Mx.{John H Maddocks - Chief Proving Officer} Rm{William Robotham - Chief Engineer}/sym.10/Jh.25.4.39. 28.G.VI. & 29.G.VI. at Brooklands. The above 2 cars were taken down to Brooklands track on Tuesday last for comparative performances and oil temperature tests. 28.G.VI. is a standard Wraith car, whilst 29.G.VI. is a Wraith car fitted with a B.60 Cast Iron engine unit. Both engines are fitted with flush top close fitting pistons, compression ratios 28.G.VI 6.15 : 1 and 29.G.VI 6.25 : 1. Rear axle ratios 8 x 34, tyres 6.50 x 17 Tyres pressures 45 lbs.sq.in. On both cars the ignition setting was T.D.C. oil used was Castrol XXL and no undershields were fitted. Petrol consumption figures were taken on the run down to Brooklands and the return journey, with the 2 cars maintaining similar speeds, and gave the following results. 28.G.VI. 29.G.VI. Derby to Brooklands. 13 m.p.g. 12.8 m.p.g. Brooklands to Derby. 14.47 m.p.g. 14.8 m.p.g. Performance figures. 28.G.VI. 29.G.VI. 10 - 20 m.p.h. 4.8 secs. 5.0 secs. 20 - 30 m.p.h. 4.0 secs. 3.8 secs. 30 - 40 m.p.h. 4.8 secs. 4.2 secs. 40 - 50 m.p.h. 5.4 secs. 4.2 secs. 50 - 60 m.p.h. 7.2 secs. 6.0 secs. 60 - 70 m.p.h. 9.0 secs. 8.2 secs. 10 - 70 m.p.h. 35.0 secs. 31.4 secs. Best lap speed 75.46 m.p.h. 79.05 m.p.h. Best half mile 79.65 m.p.h. 82.57 m.p.h. | ||