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).
Specification sheet detailing friction, transmission, valve, spring, and chassis frame particulars.
| Identifier | ExFiles\Box 32\5\ Scan143 | |
| Date | 8th February 1921 guessed | |
| Contd. -2- Friction on pivots - 8 lbs. required first initial pull from full lock. 5 1/2 lbs. from centre. Dia. of circle to turn Car. - Right hand turn. 48 ft. 6 ins. Left hand turn 49 ft. 6 ins. Length from centre of sphere to centre of axle - 72 1/4" Slack in Transmission. Top gear measured on road wheel 1 3/16" Lean of pivots - N.S. 9/16" O.S. 1/4" - measurement taken at 9 1/4" lengt Particulars of Inlet Valve. Head 1.98" Stem .3735 Length overall 6.0 Thickness of head .150 (Convex head.) Angle of seat 40° Dia. of port 1.843 Two valve springs - Particulars of small spring. Dia. of wire. .250 Length 2.525 Outside dia. 1.250 No. of coil 8 Particulars of large Spring. Dia. of wire .175 Length 3.200 Outside dia. 1.900 No. of coil 7 Working compression 2 1/8" Large spring compressed Combined spring compressed Small spring compressed 52 lbs. 2 1/8" 82 lbs. 2 1/8" 30 lbs. 2 1/8" 64 " 1 1/8" 113 " 1 1/8" 50 " 1 1/8" 80 " 1/8" 130 " 1/8" 74 " 1/8" 90 " choc-a-bloc 190 " choc-a-bloc 106 " choc-a-bloc 170 " 1 1/8" 90 " 1/8" Chassis frame is stamped out to form valences at each side, not the usual U type. Front axle pivot bearing is of one piece and is not supported at the top. | ||