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I'm currently looking for a mid 70's F100/F150 truck. I did see a 1977 F150 2WD that I could get but it has the usual 351M. I'm buying a 351W next weekend and it's going to be all fixed up nice
My question is can I put in a 351W into this truck? I was told that the 351M would most likely have a C6 tranny. If that's the case I'd put in a C4 (which I can get for pretty cheap also). How well would the 351M + C6 to 351W + C4 swap go? I hear that it all should just bolt in with no problems.
Or should I just continue my search and find a truck with a 302 or I6 which in this case the 351W should just bolt in.
You'll be better off finding a donor truck or car with a 351w to pull all the brackets and stuff. There may be some wiring issues to deal with also. You'll need cross members and motor mounts also.
The conversion is straightforward if you have a complete 351W with accessory brackets and transmission. This swap is easiest in a 302 truck like mine. Same motor mounts, same wiring harness, just different exhaust. Make sure to get front sump pan for the 351W. I had a 351M in my truck between the 302 and the 351W, if you have a complete donor vehicle it's just plug & play.
Been there, done that. It is easiest to have all accessories on the engine and have a tranny attached. You WILL have to use a tranny with the small block bolt pattern. I had a van as a donor and had to use different motor mounts for a 302 and different exhaust. The wiring was a direct plug-in(the van was a '77 also). Despite people telling me the van's center-sump oil pan wouldn't work, I measured carefully several times in several places and dropped it in with about 1-1/2" clearance between it and crossmember. Did it over a weekend and cranked it right up.
Good luck.
Kenny