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).
Letter from Ethyl Gasoline Corporation regarding views on spark plug failure and testing on various car makes.
| Identifier | ExFiles\Box 162\3\ img086 | |
| Date | 18th May 1937 | |
| COPY. ETHYL GASOLINE CORPORATION. Detroit, Michigan. May 18, 1937. Inter-office Correspondence. Mr. F.R. Banks. Dear Rod, Earl Bartholomew asked me to acknowledge and thank you for your letter of April 26th regarding the Rolls Royce spark plug situation. I thought you might be interested in my views on spark plug failure in this country. From the service angle, there has been very little spark plug cutting out at high speeds although it appeared frequently on several makes of test cars. As you know, we have carried on some tests with both Packard and Chrysler. With leaded fuel in a Dodge car, one make of plug would pretty consistently fail at 5,000 or 6,000 miles while another brand was still satisfactory at 15,000 miles. Because of this work, a lot of pressure was brought to bear on the offending spark plug company and while they made some changes, it is my belief that the new plugs are very little, if any, better than the old ones. In both the case of Packard and Chrysler a number of ignition changes were made such as voltage control generators, improvement in breaker action design and in the case of Packard, an additional coil was used. With all of these changes each make of plug functioned satisfactorily for 15,000 miles. To the best of my knowledge, neither Packard nor Chrysler have had any spark plug cutting out in 1936 or so far in 1937. The manufacturer of each part involved has, to some extent, claimed the credit for solving the difficulty and undoubtedly the main improvement was in the actual voltage delivered to the spark plug at high speeds. I do not believe the spark plug troubles we investigated were at all tied up with actual wetting of the plugs. Very truly yours, (sgd) JULIAN FREY. | ||