Are Stock LO3 heads same cc as stock L98 350 heads?
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Re: Are Stock LO3 heads same cc as stock L98 350 heads?
Re: Are Stock LO3 heads same cc as stock L98 350 heads?
Thanks for clearing that up for me Tony.So these are a good bolt on mod then? As LO3 heads are so bad flowing and heavy.
Last edited by Z28XTC; Dec 11, 2008 at 02:39 PM.
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Re: Are Stock LO3 heads same cc as stock L98 350 heads?
It depends on which L98 heads you are asking about.
The iron F-body L98 heads are 64cc's.
The aluminum Corvette L98/ZZ4 heads are 58cc's.
The iron F-body L98 heads are 64cc's.
The aluminum Corvette L98/ZZ4 heads are 58cc's.
Re: Are Stock LO3 heads same cc as stock L98 350 heads?
I got them out of a 89 Vette so I guess they are L98/ZZ4. They are aluminium and seeing they are 58cc and non LO3 swirl port heads there must be a bump in hp/tq and being a lot lighter is a plus huh?
Last edited by Z28XTC; Dec 12, 2008 at 05:55 PM.
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Re: Are Stock LO3 heads same cc as stock L98 350 heads?
hey i didn't know that, sounds like a nice addition
Re: Are Stock LO3 heads same cc as stock L98 350 heads?
It is a nice addition as I got the heads for free and I can't afford another cam swap right now (but may do in the future) even though I would like to do one(Perhaps a LT4).But as it stands it should be a nice car to drive around in and I am hoping good on gas.
Last edited by Z28XTC; Dec 14, 2008 at 07:16 AM.
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Re: Are Stock LO3 heads same cc as stock L98 350 heads?
if you got them for free it's even nicer =) let us know which ride/engine combo they are going in anyway!
just curious, would this head swap require tuning the computer as well? or would initial distributor advancing be enough to accept this modification?
and is there any difference between ZZ4 and L98?
thanks
edit: i just read this thread on nastyz28 and the one post by "Rick WI" will give you a pretty good estimation on what to expect from these heads
just curious, would this head swap require tuning the computer as well? or would initial distributor advancing be enough to accept this modification?
and is there any difference between ZZ4 and L98?
thanks

edit: i just read this thread on nastyz28 and the one post by "Rick WI" will give you a pretty good estimation on what to expect from these heads
Last edited by ownor; Dec 14, 2008 at 08:16 AM.
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Re: Are Stock LO3 heads same cc as stock L98 350 heads?
i had an engineer tell me that the lt was a half done job to the ls. so if you are doing the swap and want the aluminum one then go all the way and go ls. for some strange reason i like my iron sp no lt or ls for me. i had an aluminum engine in a 62 buick - it was not too bad, but everything was special for it. and i dont like the plastic covers you have to put on an lt or ls to cover up those ugly coils for each cylinder. it would also mean tossing out everything - like the tpi, headers and complete exhaust system, wiring, computer, transmission, everything.
but you got a great deal on the heads. i want a set of edelbrock vortec heads - 58 cc is what my freind at edelbrock says i need, myself but i sure would be a happy man with the set you got. great find.
but you got a great deal on the heads. i want a set of edelbrock vortec heads - 58 cc is what my freind at edelbrock says i need, myself but i sure would be a happy man with the set you got. great find.
Last edited by tony_cogliandro; Dec 14, 2008 at 08:21 AM.
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Re: Are Stock LO3 heads same cc as stock L98 350 heads?
i would in turn like to know what engine combo you are running 
that's what i was talking about.

Re: Are Stock LO3 heads same cc as stock L98 350 heads?
My set up is Edelbrock TES Headers,Cat removed and pipe welded in,Edelbrock Exhaust, Crane 20/20 cam,Stock L98 heads, March Under drive pulley,edelbrock intake manifold,some TBI mods (spacer etc) and a Thermostat.
Now I know these are not the best of all the Mods for making power.From what I have read on here and other forums the cam is only slightly better than stock,the edelbrock exhaust set up makes little power and the heads are both 58cc. Therefor I have a slightly over stock car.
Now I know these are not the best of all the Mods for making power.From what I have read on here and other forums the cam is only slightly better than stock,the edelbrock exhaust set up makes little power and the heads are both 58cc. Therefor I have a slightly over stock car.
Last edited by Z28XTC; Dec 14, 2008 at 11:02 AM.
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Re: Are Stock LO3 heads same cc as stock L98 350 heads?
The ZZ3 heads and the L98 Corvette heads are identical. The ZZ4 heads have better springs to handle higher lift, but are otherwise identical to Corvette heads, too.
You need to do a search for "L98 Corvette heads" and you'll find the three big problems with using Corvette heads on f-bodies.
1) No EGR passages
2) The center four bolts have the '86 and older intake bolt pattern, so the '87 and new intake manifolds require some grinding in the holes to fit.
3) They're missing one bolt to work with the serpentine accessories, so you'll need to drill and tap that hole.
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Re: Are Stock LO3 heads same cc as stock L98 350 heads?
Any major swap will benefit from computer tuning. Heck, even a stock engine will, as GM severely limited the TBI engines.
The ZZ3 heads and the L98 Corvette heads are identical. The ZZ4 heads have better springs to handle higher lift, but are otherwise identical to Corvette heads, too.
You need to do a search for "L98 Corvette heads" and you'll find the three big problems with using Corvette heads on f-bodies.
1) No EGR passages
2) The center four bolts have the '86 and older intake bolt pattern, so the '87 and new intake manifolds require some grinding in the holes to fit.
3) They're missing one bolt to work with the serpentine accessories, so you'll need to drill and tap that hole.
The ZZ3 heads and the L98 Corvette heads are identical. The ZZ4 heads have better springs to handle higher lift, but are otherwise identical to Corvette heads, too.
You need to do a search for "L98 Corvette heads" and you'll find the three big problems with using Corvette heads on f-bodies.
1) No EGR passages
2) The center four bolts have the '86 and older intake bolt pattern, so the '87 and new intake manifolds require some grinding in the holes to fit.
3) They're missing one bolt to work with the serpentine accessories, so you'll need to drill and tap that hole.
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Re: Are Stock LO3 heads same cc as stock L98 350 heads?
i had an engineer tell me that the lt was a half done job to the ls. so if you are doing the swap and want the aluminum one then go all the way and go ls. for some strange reason i like my iron sp no lt or ls for me. i had an aluminum engine in a 62 buick - it was not too bad, but everything was special for it. and i dont like the plastic covers you have to put on an lt or ls to cover up those ugly coils for each cylinder. it would also mean tossing out everything - like the tpi, headers and complete exhaust system, wiring, computer, transmission, everything.
but you got a great deal on the heads. i want a set of edelbrock vortec heads - 58 cc is what my freind at edelbrock says i need, myself but i sure would be a happy man with the set you got. great find.
but you got a great deal on the heads. i want a set of edelbrock vortec heads - 58 cc is what my freind at edelbrock says i need, myself but i sure would be a happy man with the set you got. great find.
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