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will aluminum 86 vette heads work on 87 lg4??

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Old Mar 12, 2009 | 09:36 PM
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will aluminum 86 vette heads work on 87 lg4??

i have read alot about the 113 vette heads and problems with them fitting f-body. also with the 305. now are the 86 aluminum vette heads exact same as f-body l98 heads? just alumium? can they be just bolted onto a 87 lg4? hard to find info on this setup. i might need valves etc... for these heads as the heads have been stored outside. thanks.

also these 86 heads do they use up to 86 style intake bolts or 87 up intake bolts??
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Old Mar 13, 2009 | 07:19 PM
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Re: will aluminum 86 vette heads work on 87 lg4??

First, there was no F-Car L98, it was the B2L, because of the iron heads. F-car didn't get aluminum heads until 1993. second, all the L98 vette heads kept the pre-87 intake pattern. Your heads having been stored outside, they may need to spend a night at an automotive machine shop. Once they're good, they will bolt right on to your block. You will need to use 350 head gaskets. If your LG4 is virgin, then your pistons should be about 0.025-0.030" below the decks at TDC. If so, then FelPro steelshim head gaskets are ideal. No special procedure required to use them. Be sure the decks are clean. That's it. Aluminum heads require using washers under the bolt heads, and the bolts still have to protrude from the head by at least 7/16", so check this before placing the heads on the engine. A bit of sealer on the threads, then torque to spec in thr proper sequence. Now, you'll still be around 9:1 compression, so you won't want too wild of a cam, which means you won't have trouble with the valves hitting anything. The heads have no exhaust crossover, which means the EGR won't actually be recirculating anything. But this is how GMPP's legal HO 350 conversion was, as well. The exhaust ports are a bit taller, but the aforementioned conversion used the B2L exhaust manifolds without issue.
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Old Mar 13, 2009 | 07:37 PM
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Re: will aluminum 86 vette heads work on 87 lg4??

thank you for the info. i am looking forward to this. will these heads be ok for the roller cam lt1 that i am using in the roller 87 lg4?
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Old Mar 13, 2009 | 08:21 PM
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Re: will aluminum 86 vette heads work on 87 lg4??

roller cam LT1? did you convert a '70-'71 LT-1 to roller cam, or is this a '92-'97 LT1? If the former, yes. If the latter, no.
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Old Mar 13, 2009 | 08:29 PM
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Re: will aluminum 86 vette heads work on 87 lg4??

Originally Posted by Atilla the Fun
First, there was no F-Car L98, it was the B2L, because of the iron heads. F-car didn't get aluminum heads until 1993. second, all the L98 vette heads kept the pre-87 intake pattern. Your heads having been stored outside, they may need to spend a night at an automotive machine shop. Once they're good, they will bolt right on to your block. You will need to use 350 head gaskets. If your LG4 is virgin, then your pistons should be about 0.025-0.030" below the decks at TDC. If so, then FelPro steelshim head gaskets are ideal. No special procedure required to use them. Be sure the decks are clean. That's it. Aluminum heads require using washers under the bolt heads, and the bolts still have to protrude from the head by at least 7/16", so check this before placing the heads on the engine. A bit of sealer on the threads, then torque to spec in thr proper sequence. Now, you'll still be around 9:1 compression, so you won't want too wild of a cam, which means you won't have trouble with the valves hitting anything. The heads have no exhaust crossover, which means the EGR won't actually be recirculating anything. But this is how GMPP's legal HO 350 conversion was, as well. The exhaust ports are a bit taller, but the aforementioned conversion used the B2L exhaust manifolds without issue.
umm,no f-body cars exist with L98? Please explain?
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Old Mar 13, 2009 | 09:42 PM
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Re: will aluminum 86 vette heads work on 87 lg4??

Originally Posted by Atilla the Fun
First, there was no F-Car L98, it was the B2L, because of the iron heads.
Actually, it is an L98, and a B2L as well...both the B2L and L98 RPO listed, ....here's a pic of an RPO sheet,B2L showing here as well as L98



(thanks for the thread that Okfoz put up with the above pic)

Last edited by Klortho; Mar 13, 2009 at 09:51 PM.
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Old Mar 13, 2009 | 09:53 PM
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Re: will aluminum 86 vette heads work on 87 lg4??

Originally Posted by jaygt
thank you for the info. i am looking forward to this. will these heads be ok for the roller cam lt1 that i am using in the roller 87 lg4?

The heads won't work without severe modification to them by welding up the water passages where the intake bolts to them and so on, if you have an LT1 (4th gen) motor already you have better heads than the 'vette L98 heads.
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Old Mar 13, 2009 | 10:18 PM
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Originally Posted by jaygt
will these heads be ok for the roller cam lt1 that i am using in the roller 87 lg4?
Perhaps you meant to ask, "Willl these heads be ok for the LT1 roller cam that I am using in the roller '87 LG4?"

If that is the case, then the answer is "yes".
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Old Mar 13, 2009 | 11:25 PM
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Re: will aluminum 86 vette heads work on 87 lg4??

My apologies for passing along my misinformation on the technicalities of "L98".
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Old Mar 14, 2009 | 12:05 AM
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Re: will aluminum 86 vette heads work on 87 lg4??

Originally Posted by Klortho
The heads won't work without severe modification to them by welding up the water passages where the intake bolts to them and so on, if you have an LT1 (4th gen) motor already you have better heads than the 'vette L98 heads.
THe 113 casting Aluminum L98 Corvette TPI heads WILL bolt right up using an 86 & prior manifold and work great on a 305 with NO modification needed. The LT1 cam has around .030" more lift than the L98 cam. Check the springs for coil bind and the valve seal to retainer clearance. I doubt its a problem, given the number of Corvette owners that run 1.6:1 rockers on the stock L98 cam and springs, but its worth checking. Better safe than sorry.
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Old Mar 14, 2009 | 07:52 AM
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Re: will aluminum 86 vette heads work on 87 lg4??

I was going to put that as my answer, but went back and re-read the post and it sounded like he wanted to put them on an LT1 that he currently had, other than that yes the heads will work and the cam (if it's just the cam) will work but in a 305.....eh
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