3.2 + 3.9 = Grunt? - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars

Bass Crazy · 03-25-2002, 14:44

Hey guys,

Ok, this little thought has been bugging me for a while.

I have heard of almost every man and his dog using a 302 block and heads, and installing a 351 crank and pistons etc. With a few other mods, the engins tend to get quite powerfull.

So, I then thought to myself, would it work with a 3.2L EA six, with a 3.9L crank, pistons, cam, ECU, Mainfold and injection?
Or in other words, bolt on a 3.2L head onto a 3.9L engine.

Any comments anyone?

Zomwit · 03-25-2002, 15:18

I think the 3.2 was identical to the 3.9 CFI in every way apart from the stroke. SO essentially the 3.9 CFI is a 3.2 stroker.

jamesk · 03-25-2002, 16:14

the 3.2 head has much smaller valves and ports so it wouldnt go well.
we looked into that when we took a 3.2 engine out and someone wanted to buy the head because the head on his 3.9 blew. but it didnt go very well.

Bass Crazy · 03-25-2002, 16:21

I'm sure bigger valves could be installed, and opening up the ports is an easy one.

"but it didn't go very well" , Does this mean that guy tried it?

03-25-2002, 16:30

Am I missing something here??
You put a 3.9 crank, rods, pistons etc in a 3.2L you would have yourself a 3.9 with a more restrictive than stock 3.9 head. Add a 3.9L head and you would have an exact 3.9 engine, which wouldnt go any better than a factory 3.9.

So im not sure what the point of this would be?

Bass Crazy · 03-25-2002, 16:33

A 3.9 engine with a shit load more compression because of the 3.2 head.
Well thats how the 302-351 thing works anyway.

I was wondering if these work the same way, looks like they don't.

03-25-2002, 16:35

I think BC might be thinking of higher compression by putting on a 3.2l head.
Correct me if I'm wrong.

03-25-2002, 16:36

Yep, beat me to it :)

03-25-2002, 16:43

If you want higher compression why dont you just shave the stock 3.9 head?.

What some guys with the Clevos do is is use a 351 crank, 302 rods, and aftermarket pistons. This apparently makes the engine a bit more rev happy than a standard 351 but with the same displacement.

Maybe this is what your thinking of?

Im not sure how this would work with the inline 6 though(3.9 crank, 3.2 rods), the pistons would have to be custom made though($$$$)

Bass Crazy · 03-25-2002, 16:46

I am positive the 302 head was used to up the compression. Same goes for the 289 heads on the 302.