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).
Performance graph comparing different carburetor choke sizes for a Pit Unit B.J.55 engine.
| Identifier | Morton\M19\ img292 | |
| Date | 23th September 1931 | |
| PIT UNIT B.J.55. FOR 27 EX. RM.{William Robotham - Chief Engineer} P26 23/9/31 COMPARISON OF 1 3/8 AND 1 1/4 CHOKES. 114° E82448 CAMSHAFT RR TWIN CARBS. 4.88 C/R OPEN EXHAUST STANDARD ROCKERS. ① 1 1/4" DIA. CHOKES. ② 1 3/8" DIA. CHOKES. ③ AS 2 BUT WITH AIR SILENCER. B.H.P. B.M.E.P. LBS/⎕" INDUCTION DEPN INS HG | ||