• Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.

4.0 Block and head?

addction

NAXJA Forum User
Location
Wentzville Mo.
Hey can any one tell me is a HO head will fit on a 89 Block with out any problems? I'm about 90% sure that it will but I dont want to start the stroker build & find out that the HO head wont fit. Thanks, Joe
 
The head bolts right on - but you'll end up having to bring the manifolds with it, or do some work to modify the RENIX manifolds to the HO head. There are details around here somewhere - I should find them myself one of these days... But, it's been done.

5-90
 
Bolts right on. There's a couple of holes for dowel pins in the intake, you'll need to open them towards the top since the HO has higher intake ports. I remember the sealing surface being a little thin at the top of the intake gasket and using some silicone for good measure.
 
Wasn't there an issue about water passages lining up properly...something about the head gasket...
 
The issue of the water passages of the 4.0 head possibly not lining up properly relates to the 258 block (some years), not the 4.0 block. As far as head gaskets go, the same head gasket will fit all 4.0 engines from 1987 to 2006.
 
Back
Top