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).
Table of comparative dimensions for various vehicle frames.
| Identifier | ExFiles\Box 99\2\ scan0064 | |
| Date | 25th October 1937 | |
| -3- 25.10.37. TABLE OF COMPARATIVE DIMENSIONS. DIMENSIONS. P.III. WRAITH PACKARD OLDS. VAUXHALL G.M.FRAME B.III. Wheelbase 147" 141" 121" 117" 111" 122" 124" Dash to front wheels 43" 36" 35" 28" 26" - 34" Front wheels to front of cruciform 40" 55" 37" 35" 34" 36" 34" Length " " 40" 48" 67" 74" 52" 68" 87" Rear of cruciform rear axle. 67" 38" 17" 8" 25" 18" 3" Depth of frame at front 6½" 6½" 6" 5¼" 4½" 5½" 4½" " " " centre 9" 8" 6" 5¼" 5½" 7" 6½" " " " rear 5" 7½" 5½" 5¼" 3" 3½" 3½" Depth cross at front 7" 8" 5¾" 5¼" 5¼" 7½" 6¼" " " centre 7" 9½" 6¾" 7½" 8¼" 10" 8¼" " " rear 7" 5½" 5¾" 4¾" 5" 5" 4" Width of side members 4" 2½" 2" 1⅞" 2" 2" 2⅜" " " cross 2½" 2⅜" 1¾" 2⅜" 1½" 2½" 2¼" Thickness of side members .115" .128" .145" .110" .128" .142" .104" " " cross .165" .082" .125" .090" .114" .105 x .329" .104" No. of cross members behind cross. 4 3 2 2 3 2 2 Section of frame Box Box Channel Channel Channel Channel Channel. & Box & Box & box " " cross I " " I Channel I Channel. Weight " frame 347 323 266 | ||