jwp2

So, I plan to put an LS1 from a tahoe into a 78 vette. Is it possible to use the stock 4L60E transmission ? What would I need to adapt the transmission to go straight to the drive shaft instead of the transfer case?
Otherwise...does anyone know if the stock 700R4 Trans will bolt direct to the 5.3l LS1?
Any help would be great!...JP

lionelhutz

Basically, you pull the transmission apart and install a 2WD tail shaft and then install a 2WD tail shaft extension housing. I'd highly recommend using the 4L60e with the PCM controlling the shifting before making a 700R4 work instead. You can tune or get a tuner to setup the transmission to perform much better than a 700R4 ever can.

L88Plus

4L60E doesn't have to be completely disassembled to swap the rear shaft. You'll also need the tailpiece. And I agree, stick with the electronically controlled tranny. There are a few hard parts that can be swapped to make it a good bit stronger than stock without going overboard, too.

jwp2

Thanks!
I figured it had to be something like that but wasn't sure. I am still in he planning phase but was also considering a new PCM and wire harness from GMPP...or do you think I should I try to retrofit the one from the Tahoe?

lionelhutz

You didn't tell us any info on the Tahoe, but there's no reason you can't use it, you may just want a simple PCM to use.

FYI, a 5.3L engine from a Tahoe is not a LS1. It might be a LM7 or LY5.

jwp2

You are right!...I am not very savvy on the engine designators. The Tahoe is a 2001 4wd with a 5.3 liter engine. It has 144k miles on it.

This will be a learning experience for me for sure!!

lionelhutz

That should be an easy system for a swap. The PCM should have a service number that ends in 0411 and that is one of the most widely used and hacked LS PCM's out there. So, it's perfect to start with and you should just get it flashed to remove the security and and any emissions stuff you are not running. A good shop can also throw a performance shift setup into it for you as well as adjust the tuning for headers or a smaller cam change at the same time.

East Coast Supercharging has a $150 mail in C5/C6 tuning service. They might be able to do your PCM for that too once you tell them it's going into a C3.

Otherwise, for a harness Speartech is supposed to be pretty good at it and I believe they can program the PCM so it's ready to run too.

Or, use the harness from the truck and build your own.
http://www.superchevy.com/how-to/eng...harness-build/

lionelhutz

I remembered another harness company with a good reputation - PSI or Performance Systems Integration.

Of course, there are other places like Ebay or just Google LS engine harness.

Kacyc3

check this out, he started when LT1 were the hot swaps and has followed with LS http://lt1swap.com/

jwp2

thanks so much for the recommendation! I live close to ECS so that is a great option! They have done some work for me in the past but I didn't know that they had that as a service.