1970 Mach 1 Transmission question

Mach1_1970 said:

I have a 70 Mach 1 351 Cleaveland v4 motor FMX Automatic Transmission,2nd gear does not work, I would love to put in a beefy Manual Transmission..what do I need? What would be the cost to but and install a manual zf5 speed? or to rebuild and beef up my FMX or C4? What are your thoughts on both.

Thanks

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The FMX was used on 351 rather than the C4, it was considered stronger. Simple matter to have it repaired.

If you want to convert to manual, that's another issue, but of course can be done.

obvioulsy it would be cheaper to repair the FMX. i can tell you almost without question that you broke the 2nd gear band, common problam with the FMX if you have a shift kit. make sure the transmission shop replaces the cast iron 2nd gear band with a steel flex band. other than that one weakness the FMX is a really stout transmission and the parasitic losses through the trans are about equal to a c4 and quite a bit less than a c6. i know of a few guys with really stout cars running 11's, 10's and even one in the high 9's using basically stock FMX transmisison with nothing more than good quality clutches and bands and stall convertors. one of them is a big body mach 1 (the one that runs 9's) and he can pull the wheels about 3 feet off the ground. pretty stout for an almost stock transmission.

ask about the FMX on this forum and see what kind of responses you get

http://www.network54.com/Forum/260730/