Hi-psi

Guys,

What is required, other than the heads/intake, to use the LT4 Heads and LT4 intake on a LT1? Other than the heads, are there any other differences?

I need a set of heads for my LT1. I found a good deal on a set of LT4 Heads & Intake. Is it much work to bolt these up to my LT1? I'll be using a LT4 Hotcam, Crane Gold Roller rockers, new pushrods, new studs, springs, etc.

Nathan Plemons

It'll bolt on directly. Just remember that the LT4 intake has no provision for EGR, so it's a fine opportunity to ditch that as well.

Wouldn't hurt to get those heads ported in the process if you've got the time and money.

Hi-psi

Stock LT1 heads/intake VS stock LT4 heads/intake, is there any big difference in performance #'s? Just wondering if it's worth it to make the swap or just get a set of good LT1 heads.

Nathan Plemons

Stock for stock the LT4 heads and intake will make more power than the LT1. After they are ported it's really a toss up. A really good set of LT1 heads will outflow a bad set of LT4 heads. If the shop who does your work really knows what they are doing, they can make the LT4 the superior head.

dsg049c

I just had this conversion done.. What a difference... It is costly though..
I got lucky and purchased new LT4 Heads and Intake off of EBAY. My heads were ported and polished though.. Here are the things that you will need or will want to replace..

1. Upgrade to LT4 or performance timing chain
2. LT4 Knock Module
3. LT4 Knock Sensor
4. Replace your opti-spark cap - recommended
5. Fuel pressure regulator - recommended
6. Computer reprogram (Ed Wright very good)
7. Full gasket set including oil pan gasket

I also used the Hot cam and Crane Gold RR :D :D :D
What a difference..

93 ragtop

If you go to More Performance web page, they have a article on doing a conversion. According to the article, a set of LT4 heads out of the box, (no porting or polishing) a LT4 intake, 52mm throttle body, headers, and a hot cam kit made 429 hp in the test they performed. This article makes me consider this as well

92TripleBlack

Here's all the differences and part numbers. http://home.tir.com/~steveher/lt4.html
Hope this helps.

Goody

1. The timing chain swap is costly unless you have the newer style motor as well (94+) because of the Opti. You have to change the timing cover, cam gear, add the harness for the Opti and the vent system as well. Just install a standard LT1 chain setup and it'll be fine.

2. Don't sweat the knock module unless you have a '94 or later. Doesn't work on the 92-93 years.

3. The knock sensors would also be a waste of time too unless the old ones are bad. Ensure they are torqued to a spec.

4. Not a bad idea. Corvette Fever did a story on this very thing. I did it and it has worked for me flawlessly.

5. Get an AFPR along with a new set of FMS injectors. 26 or 28# would be good, but most just go to 30# and that works too.

6. Never dealt with Ed, but heard good stuff. I've bought the equipment to do my own chips for a few bucks more. No more paying for upgrades.

7. Call Jeff Kopp at Superior Chevy at 1-800-728-8267 for the best price on all the gaskets needed for the swap. He has the best prices and lowest shipping out there. And GREAT service too!!!

Also, let me add that gmpartsdirect.com has the LT1 to LT4 kit for $2100. Can you say 100HP on a budget??


[Modified by Goody, 8:02 AM 9/25/2002]

dsg049c

This is on a 94 right?

SILVRTOY

Here you go. I can save you a ton of time. I have a 96 LT4 I'm selling in NC with 36K miles. The asking price is $23K :yesnod:

keekster

The LT1 to LT4 GM parts direct kit. Is that basically all bolt on for a 92 or is there modifications that will need to be done ?

Goody

Needs that custom chip to run right. There are other minor things to do as well, but 97% bolt on.

Goody

Seems like it. Guess I should have caught that from the signature line. My bad....My input applies to 92-93 cars then. If '94 or newer, do it your way for sure.