What tranny fits behind a 351M

[FrankenRod01]

I'm building a t-bucket. A friend of mine donated a 351 Modified engine out of a 1979 ford half ton truck for my project. It doesn't have a flywheel or transmission. For a tranny I am wanting to install an automatic, either AOD or C6. The local autowrecker can't help in finding a donor vehicle but told me that the 351 Cleveland and Windsor blocks are different than the 351 Modified. Does anyone know of a website that could give me some info? Or has anyone else done a similar project that could offer some advice on possible donor vehicles? (A 79 truck is the obvious one).
Any help would be appreciated. Thanks.

[phantom_smack]

I would not use the 351m its gonna be hard to find any performace parts for.I know they offered it with a c6 not sure about the aod though.

[doug 351]

According to my research, c6's behind 351M's are pretty commonplace and an aod is out of the question. You are basically looking for a tranny that fits the big block pattern, (400,427,460), because that's what a 351m is, a destroked 400 big block. They are a heavy smog engine that is best destintined for boat anchors, although they can be built up to make some good horsepower. It is harder to find parts, and more expensive and requires more knowledge to wring horsepower out of than the 351C or 351W. You can get a stroker kit for a 351w and easily top 400ci in a small block, whereas the 351M is 351ci in a big block. Unless your friend donated an already built up performance motor, you would be money ahead to go get a 351w or 351C core motor. The 351C was even more performance oriented than the 351W right out of the box, but tend to be more expensive to build up, because of scarcer , more expensive parts.

[mahanja]

doug 351 is correct. Scrap the 351M unless you have some wierd affinity for it. But then you are doing a t-bucket. You are going to want something cool/odd for your t-bucket. I think there are a lot better choices than a 351M that will be cool. Have you looked into a "Clevor?" Are you on a budget? So many choices... At least you aren't putting a 350 in it though.

C6 is where it's at...

[FrankenRod01]

Thanks guys. Lots of good advice. No, I'm not married to the 351M for the t-bucket project but might be able to find a home for it in my '57 mercury 1/2 ton. I didn't know the 351 was actually a destroked big block....some good info to know for the wrecking yard. Speaking of which, on my last trip to the yard I found a late 70's 3/4 or 1 ton F series truck with a 400 block and a 4 speed standard transmission.
Any thoughts on hooking up the 351M with the 4 speed for my '57?

[jonmark1985]

The four speed will work, the throws on the shifter will be huge though.

The 351M, and 400 are small blocks... Don't let people tell you otherwise. I know they use a big block bellhousing, distributor and motor mounts, but they are still a small block.

Don't believe, open the Ford Racing catalog.

[doug 351]

Originally Posted by jonmark1985

The four speed will work, the throws on the shifter will be huge though.

The 351M, and 400 are small blocks... Don't let people tell you otherwise. I know they use a big block bellhousing, distributor and motor mounts, but they are still a small block.

Don't believe, open the Ford Racing catalog.

That is correct, to an extent. That is how Ford classified the 351M- 400 series after the fact. The 400's inception was for a lightweight big block,as evidenced by the big block bellhousing, motor mounts and distributor. It's my belief that government regulations for polution controls and gas economy led to the development of the 351M, which is a de-stroked 400. Up untill that point, Ford had always upgraded it's motors by lengthening strokes, starting with the 289, going to 302 and then raising the deck and lengthening the stroke to 351W. To my knowledge, the 351M is the first time they went backwards in that respect. The 351M/400 series motors are an animal to themselves. They are most closely related to a 351C, but are a bigger motor, and way less powerful.They are not the 429/460-385 series blocks, but they use those bellhousings. They are not the "FE" series "big block", which interestingly, covers 332ci -428ci. Maybe I should have said "for all intents an purposes" a destroked big block. The jist of it remains that they are motors that have "big" blocks and IMO offer less performance than the smaller 351C and 351w blocks. It is my contention that Ford classified these as "small blocks" to save face in the fact that they did not perform to big block standards. Just MO.