Hi to everyone, thought I'd post a question for you all in this forum, I know this fella at work who's been toying with the idea of swapping out a 315M for a 390 FE, but I think it'll be alot of work. But I don't know many specifics, so I'm just wondering if this swap is even possible in a 3/4 ton 4X4 Ford so far as a bolt in procedure would go? Not sure on the exact year or if it has an auto or manual trans, as I haven't personally seen the truck. But I think it's like a 1980, 1981, or 1982. What will have to be done to make this swap work? He's very sentimental over that hopped up 390 he has lying around, but I may be able to talk him out of the swap if it's alot of work. I do know that the transmission bellhousings have different bolt patterns (351M is the same as the 429-460 big block pattern, FE big block has it's own pattern), but that's about all I know about this kind of swap. Thanks a bunch.

 

Sounds like you have a pretty good understanding of the differences. You will need a different transmission or at least a different bell-housing. You will also need different motor mounts. The distance to the t-case may also change, requiring drive shaft modifications. You may also have to hunt for necessary accessory brackets. (another good oxy-moron)

Ebay the hopped up 390, and He'll likely fetch enough to get a good start on a 460 build up.

If he's stuck on the 390, find an FE powered truck or a late 60's FE powered pony car!

The older engine may also catch the attention of the Emissions/Inspection folks, depending on where you live.

my 3 cents..