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).
Informational leaflet on the efficiency and economy of the H.V. Type Horizontal Controllable Jet S.U. Carburetter.
| Identifier | ExFiles\Box 31\4\ Scan039 | |
| Date | 1st October 1925 | |
| PRICE 1/- OCT. 1925 EFFICIENCY TO obtain the very maximum speed on a car fitted with an engine of high efficiency, it is a generally accepted fact that a choke tube of larger dimensions than standard has to be used. Its effect is that acceleration from a low speed (say, 6 m.p.h.) without changing down from top gear is practically impossible—in other words, flexibility is sacrificed for speed. Now, the S.U. Carburetter, having an infinitely variable choke controlled by the suction of the engine, the choke automatically adapts its capacity to the immediate requirements of the engine. Thus, on top gear, at say 4 m.p.h., the choke restricts itself to quite a small area, and on accelerating the area gradually enlarges whilst the engine gains speed until the maximum speed is obtained. The wonderful flexibility of this carburetter without loss of maximum efficiency is a revelation to those who can appreciate perfect carburation. ECONOMY IF any automatic type of Carburetter, not fitted with a special starting device, is set to give utmost economy when hot, then the mixture when cold will be too weak, causing difficulty in starting. Even when started, the engine will probably have to run for a period before the car can be driven away, as, until warmed up, sufficient power is not developed. With the S.U. Controllable Jet Carburetter these faults do not exist, inasmuch as the Carburetter is set to give the most economical mixture when hot, yet, owing to the jet being under the driver's control, from the dashboard, the mixture can be strengthened to ensure a dead easy start, even on the coldest morning, and owing to this temporarily enriched mixture practically full power is developed and the car can be driven straight away, without any sign of weakness. As the engine becomes warm the mixture can be gradually weakened to suit the engine's requirements, until when hot the most economical mixture is being used. The H.V. Type Horizontal Controllable Jet S.U. Carburetter THE S.U. CO. LTD. Shipton Works PRINCE OF WALES ROAD KENTISH TOWN, LONDON, N.W.5 (Nearest Tube Station: CHALK FARM) Phone : HAMPSTEAD 2413 Telegrams : "FLEXCARBUR, HAVER, LONDON" | ||