7.3 powerstroke exhaust manifold bolts

Blue 7.3 · Dec 31, 2019

Hello all,

I am currently rebuilding the top end of my 1997 f250 7.3 powerstroke. I have came across a puzzling issue and so I have enlisted here in the Powerstroke Army to see if ya'll can help. So, the exhaust manifold bolts I ordered, which is OEM Ford part number F4TZ-9 S425-A, they DO NOT fit my heads! They simply are too big for the bore, on both heads. So the only logical conclusion is that there is another part number I need? But my internet searches have been fruitless. Does anyone know another part number the 1997 heads need? Any info would be great, thanks in advance!

Blue 7.3 · Dec 31, 2019

Also, even better would be if anyone can recommend a 7.3 exhaust manifols stud kit as opposed to bolts. Thanks!

Lt.Dan · Dec 31, 2019

I'm pretty sure all the 7.3 powerstrokes (94-03) used the same exhaust manifold bolts. I've used the same kit for my 96 and 02, dunno why 97 would be any different. Maybe just drill and retap to the correct size? Seems a bigger bolt would be better anyways.

ghohouston · Dec 31, 2019

Do you already have the old manifold bolts out, and trying to install the new ones? The manifolds "warp" and become untrue to the head, making it seem like they wont fit.

Blue 7.3 · Jan 2, 2020

I'd rather not drill and tap into the heads. Might have to come down to it I suppose.

Blue 7.3 · Jan 2, 2020

Yes, the old bolts are out. When I hold the old ones and new ones side by side, the size difference is obvious. I don't understand why. Are there maybe two types of bolts Ford used?