L98 to LT1 engine swap
Thread Starter
4th Gear
Joined: Mar 2014
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L98 to LT1 engine swap
I've just inherited a 1989 c4 with most of the L98 engine missing. I have found a complete 1994 LT1 with about 80k on it locally. Is it possible and what would be the big problems?
Last edited by Avi8or; Mar 9, 2014 at 01:24 PM.
Thread Starter
4th Gear
Joined: Mar 2014
Posts: 4
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The LT1 is out of 1994 corvette, no transmission, just the engine and all or most accessories. The '89 has a THM and just a short block remains (block, pistons and crank). I'm missing intake manifold, plenum, heads, exhaust manifolds, all brackets, etc. I figure it would be easier and cheaper to find another complete motor.
Melting Slicks
Joined: May 2010
Posts: 2,082
Likes: 3
From: Conowingo Maryland
there are a few guys in the parts section that have 100% complete l98 engines. Either way it is going to cost you. Personaly I would opt for a complete L98 just because you know everything will work. And sense it is out you can have fun adding some power to it.
Racer
Joined: Jan 2014
Posts: 324
Likes: 7
From: Littleton Colorado
Putting the TH700 behind the LT1 is possible, but not completely straight-forward.
I would say the only reason to go with the LT1 is because you want an LT1.
If you just want the car running, staying with the L98 is probably the better route.
I would say the only reason to go with the LT1 is because you want an LT1.
If you just want the car running, staying with the L98 is probably the better route.
Burning Brakes
Joined: Mar 2005
Posts: 800
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How would it not be straight forward to put a 700R behind an LT1? The 92-93 LT1 is a 4L60/700R.
Intermediate
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From: IN
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Racer
Joined: Jan 2014
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From: Littleton Colorado
Le Mans Master
Joined: Sep 2006
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From: Phoenix AZ
2021 C4 of the Year - Modified Finalist
why couldn't you just use an 89 throttle body? the trans is stand alone except for the TV cable. no computer to run it.
It may throw a code for the trans, but there are people who have used an L98 distributor on an LT1 because of the optispark is not reliable.
A spacer is necessary to put the distributor high enough to ride on the cam in just the right height to mesh with the distributor gear.
this allows the use of the LT1 in an L98 car using the fuel pump, L98 computer, LT1 fuel system, and the L98 distributor, and all gauge functions would be retained.
An LT1 cooling system would have to be used. (radiator, brackets, hoses, etc.)
It may throw a code for the trans, but there are people who have used an L98 distributor on an LT1 because of the optispark is not reliable.
A spacer is necessary to put the distributor high enough to ride on the cam in just the right height to mesh with the distributor gear.
this allows the use of the LT1 in an L98 car using the fuel pump, L98 computer, LT1 fuel system, and the L98 distributor, and all gauge functions would be retained.
An LT1 cooling system would have to be used. (radiator, brackets, hoses, etc.)
Last edited by coupeguy2001; Mar 9, 2014 at 09:45 PM.
Burning Brakes
Joined: Mar 2005
Posts: 800
Likes: 2
Gotcha, wasn't thinking about the switch over to the 4L60E in 94. For that matter if it's a corvette LT1 I know for a fact the TV cable goes to the ASR instead of throttle body and if memory serves no L98 had ASR. He would still have an issue withe throttle body I believe?
Racer
Joined: Jan 2014
Posts: 324
Likes: 7
From: Littleton Colorado
It may throw a code for the trans, but there are people who have used an L98 distributor on an LT1 because of the optispark is not reliable.
A spacer is necessary to put the distributor high enough to ride on the cam in just the right height to mesh with the distributor gear.
this allows the use of the LT1 in an L98 car using the fuel pump, L98 computer, LT1 fuel system, and the L98 distributor, and all gauge functions would be retained.
An LT1 cooling system would have to be used. (radiator, brackets, hoses, etc.)
A spacer is necessary to put the distributor high enough to ride on the cam in just the right height to mesh with the distributor gear.
this allows the use of the LT1 in an L98 car using the fuel pump, L98 computer, LT1 fuel system, and the L98 distributor, and all gauge functions would be retained.
An LT1 cooling system would have to be used. (radiator, brackets, hoses, etc.)
Racer
Joined: Jan 2014
Posts: 324
Likes: 7
From: Littleton Colorado
Gotcha, wasn't thinking about the switch over to the 4L60E in 94. For that matter if it's a corvette LT1 I know for a fact the TV cable goes to the ASR instead of throttle body and if memory serves no L98 had ASR. He would still have an issue withe throttle body I believe?
Thread Starter
4th Gear
Joined: Mar 2014
Posts: 4
Likes: 0
I appreciate the responses, alot of knowledge on this board. Having done more research and evaluating the input here, I have decided it would be far less difficult to rebuild the l98. Parts seem to be plentiful and I am competent enough to build a motor, and the level of mods that would need to be done I really don't want to get into.
For those that have offered parts, I will be in contact.
Thanks Guys
For those that have offered parts, I will be in contact.
Thanks Guys