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).
Testing miniature Bosch sparking plugs on Goshawk and 40/50 engines, proposing dual ignition systems.
| Identifier | WestWitteringFiles\J\November1922\ Scan99 | |
| Date | 20th November 1922 | |
| To R.{Sir Henry Royce} from Hs.{Lord Ernest Hives - Chair} c. to E.{Mr Elliott - Chief Engineer} ORIGINAL. Hs{Lord Ernest Hives - Chair}2/LG20.11.22. X4560 MINIATURE BOSCH SPARKING PLUGS. Our tests so far with these plugs have been most satisfactory. We have tried them on the 40/50 and the Goshawk engines, in fact, they have stood up so well, that at the first opportunity, we propose trying them on an aero engine. We have written to the Bosch Co. to ask them whether they recommend these plugs to be equal to the standard dimensioned plugs and if not, what is their weakness. We have asked the D.O. at Derby to modify a Goshawk cylinder head slightly so that we can use two of these plugs on an existing engine. Apart from other advantages, it would be exceedingly useful for experimental work for us to have two independent ignitions especially when investigating ignition or other troubles. There is no doubt that if we could, without detracting any of the present advantages in the Goshawk, be able to produce cars with two independent ignitions, it would increase the value of the car in a much greater proportion than the extra cost of the double ignition. Most of the work, except for the fitting of the two plugs, has been done. One difficulty we have had is that we cannot get the two ignitions on the Goshawk (battery and magneto) to run as nicely together as we get on the 40/50 with the Goshawk battery ignition and magneto. The reason for this is that we require more range of advance on the Goshawk and therefore in order to get equal results from the magneto and battery, the hand control for the magneto requires more contd. | ||