Rolls-Royce Archives
         « Prev  Box Series  Next »        

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).
Engine heating methods, including Vee engines, the Packard 'Fuelizer', and improving low-speed performance.

Identifier  ExFiles\Box 50\3\  Scan035
Date  25th March 1921
  
Oy4 - G 25321
Mr. Claude Johnson - Sheet 3.

(a) Vee Engines (Cont'd)

It will be noticed that in the Cadillac the heat is applied to the lower side of the Tee and of the arched supply pipe.

This practice seems justified by the experiments illustrated in the S.A.E. Journal for March, which show cross sections of inlet manifolds in which the liquid potrol always hugs the lower side of the branch beyond the Tee.

(e) The Fuelizer;

This same copy of the Journal has some notes on the Packard "fuelizer" which may prove of interest. This device is not being taken up by other makers, as far as we can learn.

(f) Other heated pipes;

The new Ansted engine, an overhead valve design used on the new Lexington car, has a manifold illustrated by the enclosed cutting, in which the liquid petrol on the wall is trapped by ribs cast in the pipe, before it can enter the manifold.

An improved form of this device is illustrated in the attached cuttings, from a paper delivered by Mr. Nelson, of the Premier Motor Corporation.

(3) Necessity of Heat;

Finally we wish to inform Mr. Royce and Mr. Hives that we have found that the low speed pulling can be very much improved by fixing a pin in the throttle body as described by Mr. Hives, and this appears to overcome at least partially a slight remaining tendency to miss once or twice in getting away, which was still apparent in heated pipes, and which had puzzled us.

But the pin in the throttle, with an unheated pipe, does not in our experience overcome the main tendency for the induction pipe to "load up" when the car is driven for considerable periods at low speed and full throttle.

That is to say, a car with heated pipe and no pin in the throttle, after driving at full throttle and at 10 or 15 miles an hour for say five minutes, will get away with only one or two missed explosions, whereas the same car with a cold pipe and with the pin in the throttle will fire irregularly for several seconds before it gets under way.
  
  


Copyright Sustain 2025, All Rights Reserved.    whatever is rightly done, however humble, is noble
An unhandled error has occurred. Reload 🗙