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).
Single versus double carburetter configurations for 6-cylinder engines and their potential effects on performance.
| Identifier | ExFiles\Box 13\3\ 03-page274 | |
| Date | 2nd March 1931 | |
| HS.{Lord Ernest Hives - Chair} E.{Mr Elliott - Chief Engineer}) FROM R.{Sir Henry Royce} BY.{R.W. Bailey - Chief Engineer} ) (At Le CanadelHenry Royce's French residence.) X7080 R2/M.2.31. Copy to - SG.{Arthur F. Sidgreaves - MD} Copy to - WOR.{Arthur Wormald - General Works Manager} CARBURETTERS - 6 CYL. ENGINES. X.7080 Copy to - RG.{Mr Rowledge} X.5080. I understood that we must use double carburetters if we wanted to work with fixed throats and get good metering through the large range of speed and throttle openings used in car work. It is now suggested by HS.{Lord Ernest Hives - Chair} that for other reasons single carburetters may be preferable. This might bring us back to the type I suggested which is embodied in the down draught. Mr. Lovesey seems to prefer the single hole for edge throttle fuel supply instead of the double hole which we were told was so good on the Solex. We want to be able to completely shut the throttle and hope that even the smallest opening will give a correctly carburetted mixture. Is it possible that we can get the results we wish for by a more or less small connecting passage between the two sets of three just above the throttle; by varying the size of this passage one would expect that we could get anything between double and single carburetter effect. I am not quite in agreement with HS.{Lord Ernest Hives - Chair} that the speed range of the 6 cyl. engine can in our sizes be increased very much. Really I have only recently realised that we are getting quite up to the limit, and we have got to be content with double top and less speed range on the engine, or preferably a 12 cyl. engine which I believe will very definitely increase the speed range both lower and higher - i.e. at each end of the present. R.{Sir Henry Royce} | ||