400M engine // what heads to get?

[kalli]

Hi all, fella with an 80s Cougar had a 351M and organised a 400M stroker kit. put the block back together, all new but now realised one of the heads is cracked. what can we get as replacement (alu heads are too expensive with 950$ each) ? Will 351C heads fit? i guess they should? will the 351C fit to the 4barrel intake he had on for the 351M? anything I can measure? any ideas opinions very welcome!!!!! Kalli

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[eZ]

All of the 351C valve train components (except for the pushrods) interchange with 351M/ 400 engines. The 351M/400 cylinder heads will also interchange with the 351C 2brl heads, although the 351M/400 heads have 78.4cc combustions chamber where as the 351C 2V heads had a 76.2cc combustions chamber.

[urban_cowboy]

Do you know about these guys?
http://www.ausfordparts.com/

[THUMPIN455]

EZ nailed it, any C or M head will work, finding an intake for 4V heads would be more than a challenge, I dont think anyone has ever made one. Spacers might work, but anyway, you can make decent power with the 2v heads on a 400M. No need for anything fancy, just get some 2V heads from a C or M, they are virtually identical.

[hiboostwoody]

The M heads have a crappier exhaust runner because of the smog bumps. They still flow a TON more than your average small block head but not as good as a Cleveland head.

[rmodel65]

Originally Posted by urban_cowboy

Do you know about these guys?
http://www.ausfordparts.com/

racin ordered some of the closed chamber 2v heads took them a long time to get them to him

[kalli]

Thanks all,

I'll try to source something locally first (looking at UK). So from what I understand the 2V and the 4V heads are both 4barrell.
If we get 351C 2v heads, would you think the original 351M manifold will fit?

eZ: thanks about info with compression. i think it should be able to take a little rise. So I hope we don't end up anywhere outside the pumpgas range

Urban: thanks for the link, came across them about a year ago in a post. But as said we're trying local first (shipping will be 350$ at least from the states for a set of cast iron heads)

so from this I'll start searching for 351c 2v heads. anyone got an idea about the 351M intake if that'll fit?

Kalli

[THUMPIN455]

The M intake will fit the 2V heads, but it wont fit 4V heads. you can get an aftermarket 4 barrel intake to fit the M with 2v heads, but I dont think anyone makes ome to put 4V heads on an M. I have M heads on the Cleveland in the Cougar, they bolt right up no problem.

Here is the difference between 2v and 4v with 4v being on the left.

[kalli]

that's a massive difference alright.
found someone in UK with a full 400M engine. maybe he'll seel us the heads only.

Thanks all for the infos. I know now what'll fit and what not.