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).
Analysis of engine performance using collection bottles on carburettors and induction pipes to study fuel distribution.
| Identifier | ExFiles\Box 75\2\ scan0244 | |
| Date | 8th August 1921 guessed | |
| Oy2 - G 8821 Sheet #2. (2) Bottles: We have been using bottles a la{L. A. Archer} Dorris, first of all on the short pipe with L.H. carburetter, and upward bends, then on our standard pipe with the 1" through pipe. The L.H. carburetter gave a lot of pep to the car, but loaded up and distributed badly. Bottles on all the bends showed the reason, 1 & 6 filling up with 2 oz. of gasoline in 3 minutes when the engine was started up and run light on a hot day. On the road with the engine pulling full throttle, 3 & 4 filled up rapidly, not with heavy ends but with clear white gasoline. We thought of sloping the pipe down from the ends to the centre and putting the car on the dynamometer, as apparently the power, even with 30 cu. ins. compression space, was exceptional. But time was too valuable and the dynamometer was needed for test chassis, so we got back to the standard pipe, not before noticing, however, that the pipe which had distributed abominably and loaded up without bottles, distributed very well and refused to load up when the bottles were there and not filled up. (As soon as they filled the pipe went back to its old ways.) On the standard pipe on the dynamometer with heat passing, we have found that the bottles on 3 and 4 fill up very fast indeed when starting from cold, but that after ten minutes they practically cease to collect when pulling full throttle, except that occasionally for no apparent reason No. 2 or No. 5 will start to collect a dirty yellow collection apparently of heavy stuff quite rapidly for a few minutes and then cease. Nos. 1 and 6 collect practically nothing on the standard pipe under any conditions. The engine refuses to load up even when cold, when bottles are fitted, and begins to run steadily much sooner after starting up. It lacks the crazy flopping about of a standard pipe in the first ten minutes of running and will actually pull within a few minutes of first turning over. I cannot give you figures for this yet, but will be able to do so later. Also, shortly we shall be able to show you some distillation curves for the stuff collected in the bottles under various conditions. It really appears as though the bottle scheme is a most effective way of getting dry gas into the cylinders. (3) U.S.Methods: One can divide the induction pipe enthusiasts here into four classes, as you will gather from the discussions in the S.A.E. Journals you are getting. They are:- (a) The heaters of the intake air. (b) Those who jacket the manifolds in exhaust gas. | ||