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 table of performance data for Packard, S.3, Buick, and C.15 engines.
| Identifier | ExFiles\Box 127\1\ scan0296 | |
| Date | 7th June 1937 guessed | |
| 1086 PACARD S. 3 37 - 60 C 15 BUICK 3 ³/₁₆ 3 ³/₈ 3 ⁷/₁₆ 3 ¹/₄ 4 ¹/₄ 4 ¹/₄ 4 ⁵/₁₆ 4 ⁷/₈ DISP. 236 228 320.2 323.5 B.H.P. 93.36 @ 3200 93 @ 3600 124.4 @ 3400 125 @ 3200 TORQUE 192.9 @ 1200 168 @ 1200 254.5 @ 2000 250 @ 1600 B.M.E.P. 122.9 @ 1200 111 @ 1200 119.9 @ 2000 116.5 @ 1600 B.H.P. @ 4,000 86.09 91.0 116.7 110 F.H.P. 48.00 42.5 55.08 53 F.H.P. 3,600 3,600 I.H.P. 134.09 133.5 123.4 121.75 I.H.P. 3,600 MECH. EFF 64.2 68.2 69.1 65% @ 4000 COMP. RATIO 6.65 6.5 5.75 6.29 B.H.P. 3600 123.4 121.75 CORRECTED TO 29.92 & 60° F.{Mr Friese} | ||