LT-4 conversion?
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Melting Slicks
Joined: Sep 2003
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From: 1,000,000,001 Posts
LT-4 conversion?
Guys, I was flicking through the new Summit mag and I ran into the LT-4 Conversion kit....... Can I do this to my L-98? It's pretty pricey,, but I want to look into this a little further... Let me know
Le Mans Master
Joined: Jan 2003
Posts: 8,596
Likes: 19
From: Portland Oregon
Re: LT-4 conversion? (1990CORVETTE)
Nope, you can't install the LT4 heads onto your L98. The heads are what is often referred to as reverse cooling heads. And there are no cooling passages in the head to accomadate your thermostat.
Le Mans Master
Joined: Jul 1999
Posts: 8,683
Likes: 6
From: Phoenix AZ
Re: LT-4 conversion? (1990CORVETTE)
Well, I won't say it can't be done because I plan on putting my ported LT4 reverse-flow heads on a normal-flow 427 SBC in the near future. You just need to spend the extra money (300-400$ probably) on having the heads converted to a normal-flow configuration which CAN be done. I'm not sure if you want to spedn that much money on it though...but yes, it CAN be done.
Le Mans Master
Joined: Jul 1999
Posts: 8,683
Likes: 6
From: Phoenix AZ
Re: LT-4 conversion? (Goody)
Nope....where you going to install the distributor?? LT1/4 is under the waterpump on the front of the engine. Think super ram.
Le Mans Master
Joined: Jan 2003
Posts: 8,596
Likes: 19
From: Portland Oregon
Re: LT-4 conversion? (Zix)
Are you doing the installation because you already own the heads? Why not just sell them to a LT* owner and buy some new heads made to work on your L98? Or is the cost offset that much? Just curious :) For that 427 I would want some 220 or 227 AFRs or perhaps even a set of 215 Raised runner heads for some big Hp.
[Modified by tjwong, 11:41 AM 1/2/2004]
[Modified by tjwong, 11:41 AM 1/2/2004]
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Re: LT-4 conversion? (tjwong)
They will bolt up but theyre setup for reverse cooling, its also using an updated version of FI, and has no distributor in the manifold.
You would end up having to spend more money to update your computer, and having it setup for standard cooling. Not worth it, and unless you updated the FI then I bet it wouldnt give the HP they advertise.
You would end up having to spend more money to update your computer, and having it setup for standard cooling. Not worth it, and unless you updated the FI then I bet it wouldnt give the HP they advertise.
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Le Mans Master
Joined: Jul 1999
Posts: 8,683
Likes: 6
From: Phoenix AZ
Re: LT-4 conversion? (tjwong)
They are heavily worked over, and have the best of everything, Ti retainers, big duel springs, copper-bril. exhaust...they flow over 310CFM @600. The intake runners on these heads are almost 227cc now if I remember right. They are too perfect for a nice 427, plus the machine-work alone on the heads/intake cost me about 3000$...which was a favor, the normal price would have been in the 4000$+ range. I thought about getting a new set of heads but after looking into converting them there's no need, the conversion is actually pretty simple as long as you have someone competent do the job.
I thought about the rasied runner heads too, and am actually in the process of helping a friend put a set on a 383 Bowtie block now, we have to cut and re-weld his mini-ram for them to work properly and that's more than I want to do...plus the extra expense of getting a mini-ram just to spend more to have it hacked and welded didn't appeal to me. When for around 300$ (give of take 100$) I can use the setup I have now. I won't be the first to do this, I've talked to a couple people that have done it already and have had good results.
I thought about the rasied runner heads too, and am actually in the process of helping a friend put a set on a 383 Bowtie block now, we have to cut and re-weld his mini-ram for them to work properly and that's more than I want to do...plus the extra expense of getting a mini-ram just to spend more to have it hacked and welded didn't appeal to me. When for around 300$ (give of take 100$) I can use the setup I have now. I won't be the first to do this, I've talked to a couple people that have done it already and have had good results.