Will a '77 302 and a 351C mate up to the same FMX transmission? . . . not at the same time of course.

Running the 351C / FMX now. I've got a good '77 302 I'd like to run in front of the FMX while I decide what to do with the 351C.

Is this a straight forward swap?

Mitch

 

Im new to the forum, but growing up in a salvage yard I can tell you,,, yes. The 300 six, 302, and 351w and 351 c all share the same bell housing,,,, the only trouble you may run into is flywheel size at the bottom,,, but dealing with a truck( I assume) yes they arew the same,,,,,

 

That's true for about 99% of 351c's. There are a few of them from the first production year that had 460/351m/400 bellhousing patterns.

At least, that's what I've read on this forum from people I trust. I've never seen one in person.

 

Thanks guys. I've had the 351C and fmx in my old truck for several years. I quit driving it bad in '99 when the tired old 351 wouldn't hold good oil pressure. As best I remember, the fmx leaked, but worked well when I quit driving it.

I'm trying to get the old pick up running again with out sinking a lot of money into it. I just bought a good 302 and C4 to put in the truck. Found this setup at a price I couldn't pass up.

Trying to decide whether to include the C4 in the swap, or just swap the engines and try the fmx.

Mitch

 

Just from an effort standpoint it's a lot easier to swap both motor and tranny at the same time.

 

I agree Andy. The reason I'm pondering over this is, if I stay with the transmission that's already in the truck, I know I wont have any drive shaft issues to deal with. I don't know yet if the shaft I'm running now is gonna work with the C4 transmission.

Mitch

 

It's pretty easy to change a driveshaft, but it's a lot more work to separate both tranny's, bolt the FMX up to the 302, install it, find out it doesn't work, and then either drop it and rebuild it or put the C4 in there and have to deal with driveshaft lengths anyway.

On the other side, putting a C4 where an FMX once was can create problems too. TV cable (if a C4 has such a thing), vacuum lines, shifter linkages, tranny mounts, etc. are all potential gotchas.

Just some food for thought. Good luck with whichever approach you take.

 

The 77 302 wil bolt right up to the FMX, uses the same 351C flexplate, same motor mounts. Nothing fancy or mysterious about what you're doing here. Go for it. The FMX is a far tougher transmission in stock form than a C-4. Only hard part is getting parts for it now. If not mistaken both the FMX and C-4 are the same length, only difference there is the slip yokes, the FMX uses a 31 spline yoke, the C-4 uses a 28

 

what about a 1964 F100 with a Borg-Warner T98 tranny? The truck still has it's stock 223 I6. What other engines will bolt up to that tranny before major mods have to be done? Thanks for any info