hello i have a 77 ford f-100 that had a 351m with a 4 speed man. trans. in it, but the engine had a crack in it so im in the process of swaping it for a 351m out of a 78 thunderbird that had a auto trans in it, i went to try to line the engine up to the bell housing and the bold patterns are different, what should i do, buy a new housing, make an adaptar plate ?? please help thanks tye

 

you have a different motor out of that t-bird... remember that cars came with a 351W, which has the small block ford pattern.

351M has 8 valve cover bolts, W has 6.

 

um yes its a 351m i checked the bolt pattern and the valve cover had it listed as a 351m also but thanks for the info ......tye

 

there is no difference in the bolt patterns then, you are doing something wrong.

 

I agree. If you know that the motor from the T-Bird is a 351m then the motor in the truck has to either be a small block or an FE. Not much else it could be.

 

The FE was killed off earlier than that. It has to be a small block or someone swapped a cleveland into there which is extremely similar to the modified cleveland motors. The cleveland does have the small-block bellhousing, too. Even if its a 370 baby big block, it'd have the same bellhousing.

 

I have a 1978 f-150 300 i6 with an np435 four speed i was wandering if a 351m (from another 78) would bolt up to my bell housing?

 

no. The 300 I6 uses the small block ford (289,5.0,351W) pattern.

 

You could change the bellhousing on the tranny. It then would bolt up. Im not sure about the engine mount towers though. The 351m/400m engines have the same engine mount towers as the 302/351 but I dont know if the I6 has different ones than those. So basically if you want that engine in your truck you need some small block engine towers and a big block bellhousing from a 351m,400m,429,460...there are some more but I know those off the top of my head. Hope this helps.

Ryan

 

If the bellhousing is indeed different then I would say that at some point in time somebody swapped a 351C into one of them the Clevelands and 351m/400 used the same heads.

 

That's what I would say too. I think one had a small block pattern and the other the big block.

 

The 300-6 has vastly different mounts than any v-8

 

They're talking about the transmission bellhousing bolt pattern.

 

thanks for the help

 

I realize that he is refering to the bellhousing patterns, but if you are identifing the motor from the valve cover bolts 351c and 351m used the same heads. Although the 351c is a small-block pattern and the 351m is a big-block pattern on the bellhousing.

Is the thermostat housing on both engines located on the block and not the intake manifold?