Crate L98
Thread Starter
Racer
Joined: Aug 2008
Posts: 302
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From: Lebanon MO
Crate L98
Where can I get a crate motor to replace my 87 L98? I've heard that the ZZ4 is the latest. Can I keep my intake and fuel system to keep from having to replace a bunch of stuff? Any ideas where to get from a reputable place? Valve guides &/or seals need replaced, about $500 locally. 82000 miles, so I figure why not refresh everything. Any ideas?
Team Owner
Joined: Sep 2001
Posts: 62,137
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From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
ZZ4 is the closest thing available to the later L98, and you can put all your stock stuff on it and it'll run fine. The cam is a little bigger than what you have, but the ECM will run it without a new custom chip fine.
Just know that it wont make anywhere near the 350hp rating once you put the stock stuff on there.
Just know that it wont make anywhere near the 350hp rating once you put the stock stuff on there.
Advanced
Joined: Mar 2006
Posts: 99
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From: Mesa AZ
Try this web site
I have a ZZ4 in my '90. Go to: gmperformanceparts.com then enter part number 24502609. That's what I bought. You can even enter your zip code to find someone near you. Ask lots of questions. Good luck.
Corvette Enthusiast
Joined: Oct 2007
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From: So. Cal.
2025 C7 of the Year Finalist- Unmodified
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crate motor
I bought my crate motor directly from GM. I ordered the origanal equipment replacement. I love it. Very reliable and have never had any issues. My vette is not my hot rod so the oem engine meets my needs. I get in one of my BBC cars to go fast!
Le Mans Master
Joined: Dec 2004
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From: Myrtle Beach SC
St. Jude Donor '05-'06
Thread Starter
Racer
Joined: Aug 2008
Posts: 302
Likes: 0
From: Lebanon MO
ZZ4 is the closest thing available to the later L98, and you can put all your stock stuff on it and it'll run fine. The cam is a little bigger than what you have, but the ECM will run it without a new custom chip fine.
Just know that it wont make anywhere near the 350hp rating once you put the stock stuff on there.
Just know that it wont make anywhere near the 350hp rating once you put the stock stuff on there.
Would it be better to rebuild this one, and put in bigger cam, and possibly AFR 180cc heads ($1300)??
Team Owner
Joined: Sep 2001
Posts: 62,137
Likes: 1,727
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
Note that the ZZ4 is rated with a carb, carb manifold, and open exhaust.
You will need at least a Miniram/LT1 intake and headers, then a custom chip burned because of tip-in issues with this intake. That will cost in the $1500-2000 range if you buy it all new so best look on ebay.
But, you can build it to make 350, it will still need a new intake system. How much it all costs will depend on exactly what power you want to make, how much work you can do yourself, what intake you decide to use, etc. My website has suggestions, click my name and you'll find it.
You will need at least a Miniram/LT1 intake and headers, then a custom chip burned because of tip-in issues with this intake. That will cost in the $1500-2000 range if you buy it all new so best look on ebay.
But, you can build it to make 350, it will still need a new intake system. How much it all costs will depend on exactly what power you want to make, how much work you can do yourself, what intake you decide to use, etc. My website has suggestions, click my name and you'll find it.
Le Mans Master
Joined: Jun 2006
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From: One day you're a Comet...the next day you're dust... Arkansas
What would I be looking at replacing to get the 350hp. I would still like to keep fuel inj for reliability. Would the LT1 intake or something like that work?? I'm new to all of this, that's why for all the ??
Would it be better to rebuild this one, and put in bigger cam, and possibly AFR 180cc heads ($1300)??
Would it be better to rebuild this one, and put in bigger cam, and possibly AFR 180cc heads ($1300)??
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Le Mans Master
Joined: Aug 2007
Posts: 8,735
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From: WV
Check out this company, I spoke to them a few weeks ago and was told they could send me a motor they have in stock, have one built,or I could send them my motor and have it built to whatever specs I wanted. They also have Performance crate motors at very good prices. Most motors come with 8 year 80,000 mile warrenty...
http://www.usengine.us/?gclid=CKPc1q...FSVPEAodhR6HlQ
http://www.usengine.us/?gclid=CKPc1q...FSVPEAodhR6HlQ
Last edited by WW7; Sep 9, 2008 at 04:21 PM.
Thread Starter
Racer
Joined: Aug 2008
Posts: 302
Likes: 0
From: Lebanon MO
Thanks for the advice. I was wondering about some of these power adders I've seen in catalogs, and wondering if they really worked.
I've got FlowerMaster exhaust, but I think that is it.
I look into getting the rest of the exh done first. I'm not going to 1/4 mi drag, just street driving. What suggestions on heads. Mine are in need of seals and guides. Should I replace w/AFR, or just redo mine. I thinking about the bigger runner and intake. I guess my question is, is replacing the heads by themselves an improvement without doing anything else, like cam, comp, etc.. Are AFR that much of an improvement of redone stock heads. (I think they quoted 180cc @$1300 vs $500 to redo mine locally) Like i said before, not going drag racing
, but who couldn't do with a little power power right. 
I've got FlowerMaster exhaust, but I think that is it.
I look into getting the rest of the exh done first. I'm not going to 1/4 mi drag, just street driving. What suggestions on heads. Mine are in need of seals and guides. Should I replace w/AFR, or just redo mine. I thinking about the bigger runner and intake. I guess my question is, is replacing the heads by themselves an improvement without doing anything else, like cam, comp, etc.. Are AFR that much of an improvement of redone stock heads. (I think they quoted 180cc @$1300 vs $500 to redo mine locally) Like i said before, not going drag racing
, but who couldn't do with a little power power right.
Le Mans Master
Joined: Jun 2006
Posts: 5,642
Likes: 5
From: One day you're a Comet...the next day you're dust... Arkansas
Thanks for the advice. I was wondering about some of these power adders I've seen in catalogs, and wondering if they really worked.
I've got FlowerMaster exhaust, but I think that is it.
I look into getting the rest of the exh done first. I'm not going to 1/4 mi drag, just street driving. What suggestions on heads. Mine are in need of seals and guides. Should I replace w/AFR, or just redo mine. I thinking about the bigger runner and intake. I guess my question is, is replacing the heads by themselves an improvement without doing anything else, like cam, comp, etc.. Are AFR that much of an improvement of redone stock heads. (I think they quoted 180cc @$1300 vs $500 to redo mine locally) Like i said before, not going drag racing, but who couldn't do with a little power power right.
I've got FlowerMaster exhaust, but I think that is it.
I look into getting the rest of the exh done first. I'm not going to 1/4 mi drag, just street driving. What suggestions on heads. Mine are in need of seals and guides. Should I replace w/AFR, or just redo mine. I thinking about the bigger runner and intake. I guess my question is, is replacing the heads by themselves an improvement without doing anything else, like cam, comp, etc.. Are AFR that much of an improvement of redone stock heads. (I think they quoted 180cc @$1300 vs $500 to redo mine locally) Like i said before, not going drag racing
, but who couldn't do with a little power power right. 
Thread Starter
Racer
Joined: Aug 2008
Posts: 302
Likes: 0
From: Lebanon MO
I wouldn't bother with porting the 128 heads. If you want to do a little now, freshen your heads with a 3 angle valve job and use 1.6 full RR's and new springs and keepers. Install a TPiS ZZ9 cam and LT headers like Hedman Elites. If you shop carefully you can get all those parts for under $1000. That should add over 50 HP. Forget the catalog adders, they are a rip off. DO SOME RESEARCH!
what is 1.6 full (roller rockers?) Is this a ratio of some kind? I haven't taken mine apart yet. I understand from reading posts, that it has r/lifter, but not rockers, right?
LT headers= Long tube vs shorties? What is the performance difference?
TPiS ZZ9 cam. What brand is this, and where is best value. Lift, duration? Do I need this when I order new springs and rockers? Will rockers fit under stock covers? Sorry if I'm picking your brains too much, just trying to learn.
Team Owner
Joined: Sep 2001
Posts: 62,137
Likes: 1,727
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
Yes you have a roller cam, but a roller rocker is on top of the valve, it has less friction than the rockers you have now. They give roughly a 10-15hp gain. The stock rocker cover drip tabs must be ground down for them to clear.
The suggestion on heads is entirely dependent on what power goals you have, and what intake you want to run. If you only want to freshen it up with a little more, then I'd go for Edelbrock RPM 170cc heads, anything bigger and I'd need to know exactly what you want out of it and answers to the other questions I gave you above.
The argument over longtubes vs. shortys has been hashed out before, try searches in the archives first. Emissions laws in your state must be considered.
TPiS is its own brand. Any cam change needs the right springs, and results depend on the intake youre going to run.
All of this depends on what your goals are and what intake you want to run. This is all to be put in as a matched combination.
Judging by your knowledge now, you must do alot more research on these engines before you jump into this project. Get a few books and work through the search function.
The suggestion on heads is entirely dependent on what power goals you have, and what intake you want to run. If you only want to freshen it up with a little more, then I'd go for Edelbrock RPM 170cc heads, anything bigger and I'd need to know exactly what you want out of it and answers to the other questions I gave you above.
The argument over longtubes vs. shortys has been hashed out before, try searches in the archives first. Emissions laws in your state must be considered.
TPiS is its own brand. Any cam change needs the right springs, and results depend on the intake youre going to run.
All of this depends on what your goals are and what intake you want to run. This is all to be put in as a matched combination.
Judging by your knowledge now, you must do alot more research on these engines before you jump into this project. Get a few books and work through the search function.
Last edited by vader86; Sep 9, 2008 at 10:46 PM.
Melting Slicks
Joined: Feb 2005
Posts: 2,057
Likes: 5
From: Bay Shore, NY
Factor in the cost of the ZZ4 and whatever you will need to make it work for the results you are looking for. Then shop around your neighborhood for a respectable engine builder and get a quote on rebuilding what's in the car now with whatever gains you desire. I can probably bet it would be more cost effective for the rebuild. Just my 2 cents.
