90 vs 88 head
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Joined: May 2001
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From: New Jersey
The head from the 1990 is a "better" head. The main change was the casting thickness was increased near a few bolt holes that were starting to show cracking in the old design.
The 1990 head is a direct replacement, but you'll need a couple of longer head bolts.
Edit-I see you want to put the head 88 head on the 90. You can, but you'll need a few shorter bolts. Depending upon the damage to the 90 head, it may be better to fix than replace with the earlier head.
The 1990 head is a direct replacement, but you'll need a couple of longer head bolts.
Edit-I see you want to put the head 88 head on the 90. You can, but you'll need a few shorter bolts. Depending upon the damage to the 90 head, it may be better to fix than replace with the earlier head.
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Joined: Aug 2005
Posts: 1,371
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From: Muncie, Indiana
Originally Posted by John Veninger
The head from the 1990 is a "better" head. The main change was the casting thickness was increased near a few bolt holes that were starting to show cracking in the old design.
The 1990 head is a direct replacement, but you'll need a couple of longer head bolts.
Edit-I see you want to put the head 88 head on the 90. You can, but you'll need a few shorter bolts. Depending upon the damage to the 90 head, it may be better to fix than replace with the earlier head.
The 1990 head is a direct replacement, but you'll need a couple of longer head bolts.
Edit-I see you want to put the head 88 head on the 90. You can, but you'll need a few shorter bolts. Depending upon the damage to the 90 head, it may be better to fix than replace with the earlier head.
Rod
Three Wheelin'
Joined: Apr 2004
Posts: 1,868
Likes: 4
From: San Diego, CA USA
When my '88 S4 heads were exchanged for rebuilt units, the rebuilt units I got WERE CRACKED at the bosses where the head bolts mount.
I would encourage you to stick with the thicker bosses of the GT heads and would discourage you from using earlier S4 heads.
You probably won't have any problems, but IMO it's relatively cheap insurance. It's a big job to swap heads.
I would encourage you to stick with the thicker bosses of the GT heads and would discourage you from using earlier S4 heads.
You probably won't have any problems, but IMO it's relatively cheap insurance. It's a big job to swap heads.
