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Can a 4.0(88?) be change4.0h-o y/n??


NAXJA Forum User
milwaukee WI
looking for info 4.0h-o Can i us 88 block4.0not h-o. and put all of 92h-o on it &how can I find out the year the dealers & bone yards cant help!!ps ihave the block #
I'm not clear from your post which way you want to go, but the anser is a qualified "yes."

The lower short block will interchange with no problems. The heads are different between the Renix years (87 - 90) and the HO years. The difference is in the port shape and height. There are ways to modify the manifolds to work with the "wrong" year heads, but the easiest way if the head is usable would be to swap the head from the vehicle onto the replacement block.

Also note that you will have to use the flywheel or flex plate that was in the vehicle. The Renix and HO engines use completely different computers and ignition/injection systems. The CPS operates on a different principle and the flywheel notches for one won't work with the other.
And dont forget the Gauge Temp sensor hole at the rear left of the head in not thier..........................
you can bolt up the newer head to the old block and leave all your old stuff on if all you are looking to do is replace the head. i have my 88 manifolds mated to a 94 block and head, didnt modify anything, just bolted it up as it was on the 88 block and head. ports are slightly different but doesnt change anything, mine runs great.