I am installing an engine for a guy, he has a 97 GMC Jimmy with a 4.3, he bought a wrecked 91 jimmy with a 4.3 for the engine. he rebuilt the heads on the old engine and installed them with the intake off of the 97, during installation there were several complications with things being different, the exhaust manifolds are different and wont work for one thing. my question is: do the '97 intakes work with the older style heads? evrything is bolted on i ask him if the intake ports lined up and everything and he said ' he thinks '. i jumped into this right in the middle and had to undo everything they did and redo it, otherwise this stuff would not have been an issue. sorry for the long post.
CK5
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another question for Gm mechanics
- Thread starter 35dp
- Start date
Slapperbar
Retired Navy NDT Examiner
Didn't the later 4.3's have a balance shaft. Me thinks so.
Slapperbar
Retired Navy NDT Examiner
I don't recall, someone around here should.
Jason4x4
1/2 ton status
the 97 4.3 a vortec, which is like the 5.7 vortec, it only has 8 bolts that hold the intake on instead of 12.
Dafey
1/2 ton status
Go over here and ask them,it`s just as good a site as this one.
http://forums.s-series.org/index.php
http://forums.s-series.org/index.php
914.3 vs 97 4.3
I remember when we sold reman engines that they were different engines and couldn't be switched. Plastic vs metal timing cover, vortech vs non vortech.
If that helps
I remember when we sold reman engines that they were different engines and couldn't be switched. Plastic vs metal timing cover, vortech vs non vortech.
If that helps
They are as different between those years as the old 350's and the Vortec 350's. It's not a straight swap at all.
Dafey
1/2 ton status
Did you ask them about the shaft. I remember there being a LOT of threads about that like a yr ago.But I was only reading out of boredom , I wasnt really intrested enough to pay that close attention to remember.
lectric80
3/4 ton status
The intake will not interchange. You would need the heads from a 97 to make this swap work. The ports are totally different, as is the number of bolts holding the intake on. The 91 should be a CPI or TBI engine, while the 97 will be a TPI system.
