Thread: 32 Roadster Identification

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Well that is my first mistake this year. I yield to Mick and Bob. I understand about the "parallelogram" aspect of the four bar link and we do seem to agree that the I-beam can twist a bit (although I find it hard to believe it flexes more than a few thousanths of an inch). Anyway I went through that thought process backwards intending to use split wishbones first from a Model A front end and then considered a '40 Ford front end so I have been thinking I-beam all along. When two Model A frames turned out to have rust problems I bit the bullet for a Brookville frame which arrived with a four bar set up and I purchased a 5" drop I-beam so now I have an I-beam four bar which is OK as far as I can tell. So a four bar set up is OK with either tube or I-beam axels but the tube does need the four bar for less stress. The way I got to this thinking error was in considering split wishbones to save money and in either case ('40 or Model A) the "knuckle" of the wishbone on the axel boss would have provided a twist on a tube axel which the four bar is designed to eliminate or reduce. I note that the original stock Ford front end mounting placed the wishbone center on a "ball joint" to allow side-to-side play and that it is the act of splitting the wishbones that causes the axel twist. Apparently the four bar mount solves this problem and the main cause for alarm is the split wishbone configuration. Sorry about the confusion.

Don Shillady
Retired Scientist/teen rodder