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).
Comparing the performance figures of the Phantom I, Phantom II, and Cadillac V16 engines.
| Identifier | ExFiles\Box 125\1\ scan0059 | |
| Date | 14th October 1930 | |
| X1)29. October 14th, 1930 To: Mr. Burton From: Mr. Olley CC -- Mr. Beaver Mr. Caswell CADILLAC V16 If the figures given by Strickland in SAE Journal for August are true, they should be very useful in getting Hs.{Lord Ernest Hives - Chair} to appreciate the vital urgency of real power increase. Undoubtedly, they refer to open exhaust, but even so they are remarkable. English figures for PI and PII are with cut-out open. The V16 weighs over 6000 lbs., but some of our heavier PI jobs are not far off, and the lower gear ratio of the V16 ( apparently 4.39 against our 3.72 ) with the higher-speed engine should make the V16 an extraordinary performer. It shows also the vital necessity of keeping weight down on PII coachwork in order to take advantage of the lower chassis weight which is almost back to Silver Ghost figures, 300 lbs. lighter than PI. Here are the figures:- Engine PI PII V16 Engine Comp. Ratio 4.25 4.6 5.5 Cylinder 4¼ x 5½ 4¼ x 5½ 3 x 4 Displacement 468 cu. ins 468 cu. ins 452 cu. ins Ax. Ratio 3.72 3.72 4.39 Power MEP Power MEP Power MEP 500 R.{Sir Henry Royce} P. M.{Mr Moon / Mr Moore} 30 101.5 30 101.5 28.5 100 1000 R.{Sir Henry Royce} P. M.{Mr Moon / Mr Moore} 59 100 60 101.5 60 105 1500 R.{Sir Henry Royce} P. M.{Mr Moon / Mr Moore} 85 96 89 99 90 105 2000 R.{Sir Henry Royce} P. M.{Mr Moon / Mr Moore} 102 86 112 94.5 112 98 2500 R.{Sir Henry Royce} P. M.{Mr Moon / Mr Moore} 105 71 125 84.5 135 95 3000 R.{Sir Henry Royce} P. M.{Mr Moon / Mr Moore} -- -- -- -- 156 91 3500 R.{Sir Henry Royce} P. M.{Mr Moon / Mr Moore} -- -- -- -- 146 73 Oy. | ||