Replacing my '91 L98
Thread Starter
2nd Gear
Joined: Jul 2004
Posts: 2
Likes: 0
Replacing my '91 L98
My 91's L98 is on it's last legs. The dealer could not sell me a new long block. West Coast Corvettes recommended the ZZ4, though this is not Calif smog legal. Any suggestions on a replacement engine? Is the AC Delco 383 a good engine. Thanks for the help.
Heel & Toe
Joined: Jul 2004
Posts: 16
Likes: 0
From: Herculaneum Mo
Maybe someone else can comment on this engine, but I found it interesting. Dont know if its Calif. legal though.
http://www.sdpc2000.com/cart.asp?act...=1577&pid=9009
http://www.sdpc2000.com/cart.asp?act...=1577&pid=9009
Melting Slicks
Joined: Sep 2001
Posts: 3,494
Likes: 36
From: Livermore Ca
St. Jude Donor '05-'06
Originally Posted by Seahawk
My 91's L98 is on it's last legs. The dealer could not sell me a new long block. West Coast Corvettes recommended the ZZ4, though this is not Calif smog legal. Any suggestions on a replacement engine? Is the AC Delco 383 a good engine. Thanks for the help.
Le Mans Master
Joined: Feb 2002
Posts: 5,970
Likes: 20
From: San Marcos Texas
That engine above has Iron heads. Why not just rebuild your engine? buy a stroker kit(complete rotating assembly) and have your block bored and honed. Your heads are aluminum, have them rebuilt. Then bolt on all your original parts and it will look stock. That way you can pick your own cam and pass smog checks. There are also other engine builders that can build you an engine to suit your needs. You need to stay with the aluminum heads either way. 
Last edited by chriswtx; Jul 31, 2004 at 06:30 PM.
Le Mans Master
Joined: Feb 2002
Posts: 5,970
Likes: 20
From: San Marcos Texas
Also the ZZ4 should work just fine, the only reason its not smog legal is because it comes with an intake manifold for a carb and a vacum advance distributor. If you bolt up all of your fuel injection and smog stuff nobody will ever know. And the cam it comes with is almost the exact same cam in the 91 Corvette. The ZZ4 is perfect for your needs. You will have to put a corvette water pump on it and use your distributor. Everything else should bolt right up..
I still say just rebuild your engine. Find a good machine shop and have them do it for you.
I still say just rebuild your engine. Find a good machine shop and have them do it for you.
Last edited by chriswtx; Jul 31, 2004 at 06:38 PM.
Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
Originally Posted by chriswtx
That engine above has Iron heads. Why not just rebuild your engine? buy a stroker kit(complete rotating assembly) and have your block bored and honed. Your heads are aluminum, have them rebuilt. Then bolt on all your original parts and it will look stock. That way you can pick your own cam and pass smog checks. There are also other engine builders that can build you an engine to suit your needs. You need to stay with the aluminum heads either way.
Le Mans Master
Joined: Feb 2002
Posts: 5,970
Likes: 20
From: San Marcos Texas
The ones in the pic look like steel vortec heads. There is no mention of aluminum heads in the ad.
Also summit racing sells the GM ZZ4 engine for $3895 part #NAL-24502609. You could probably find it cheaper a GMpartsdirect.com.
Also summit racing sells the GM ZZ4 engine for $3895 part #NAL-24502609. You could probably find it cheaper a GMpartsdirect.com.
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Instructor
Joined: Feb 2004
Posts: 144
Likes: 0
From: San Bernardino Ca
what I did was to rebuild my block it's at .30 over and bought a zz4 cam for $140 the rest of the stuff is stock and some memnbers told me that it would pass smog I was also concerned because I live in Cal.
But I think that it will pass and since it is mild it should not be a problem
I hope
But I think that it will pass and since it is mild it should not be a problem
I hope
Le Mans Master
Joined: Feb 2002
Posts: 5,970
Likes: 20
From: San Marcos Texas
Ouch, thats high. With the coast of a ZZ4 at $3800 plus where I work we charge $700 labor for a motor install. That would coast you about $4500 plus the misal. hoses, gaskets, fluids and stuff figure another$500-$600. So for around $5000 you can get it done at my shop. About $2000 cheaper. I would look around for other shops. If you lived in Texas I would say come see me.