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).
From Mr. Olley to Mr. F.H. Royce regarding various types of spark plugs and the testing of a Champion Toledo plug.
| Identifier | ExFiles\Box 35\3\ scan 113 | |
| Date | 22th May 1920 | |
| X4196 OY3/G22.5.20 May 22nd. 1920. To Mr. F.H. Royce. c.c. Mr. Hives. Mr. Elliott. Mr. Nadin. Mr. Caswell. From Mr. Olley. RE SPARK PLUGS. X.3905 X.4196 X.3722 X.1812. In reply to your R9/G27.3.20, the following spark plugs have been sent to either Mr. Hives or yourself. Herz Spark Plugs. B.G. Spark Plugs. New type A.C. Spark Plug. New type Champion Spark Plug. New type Herz Spark plug. Of course, it has not been possible to make a real test on the single samples which I brought over, but we would be glad to know whether you think that all of these plugs would prove unsatisfactory on the cars. The plug of which we have used the greatest quantities here is the Champion Toledo Metric Regular, which is a very simple type of single/point plug with special hard porcelain insulation. Two sets of a revised and improved modification of this plug have lately been sent to Mr. Caswell for test, with a view to his finding out whether they give better results than the old plugs. We think that they should do so as they have stouter electrodes. As far as we can find out by reference to Mr. Caswell's experience, and the experience of others, the two best makes contd:- | ||