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 specifications of a 'Measuring Autovac' with a 'Standard Autovac'.
| Identifier | ExFiles\Box 40\4\ Scan166 | |
| Date | 12th June 1925 | |
| R.R. 493a (50M) (D.D. 24. 12-6-25) J.H.D. EXPERIMENTAL REPORT. -5- Expl. No. REF HS{Lord Ernest Hives - Chair}/AJL/LG9.12.25 Instead of the standard useful capacity of .9529 galls. it is reduced to .670 galls. or a reduction of 29.6%. This loss of course will increase the probability of drying up. The following are particulars of the Measuring Autovac as compared with Standard Autovac :- | | Measuring Autovac. | Standard Autovac. | |---|---|---| | Dia. of float. | 3.22" | 3.0" | | Dia. of float chamber. | 3.375" | 3.375" | | Stroke of float. | 0.65" | 0.3" | | Petrol sucked per stroke. | Tank empty 98 cc's Tank full 92 cc's. | 50 cc's by measure-ment. | | Distance from face to float chamber to bottom of flap valve. | 6.3425" | 5.5" | | Useful capacity of Phantom tank. | .9529 galls. | .670 galls. | Hs{Lord Ernest Hives - Chair}/A.J.Lidsey. | ||