I’m not even sure how to begin, but here goes:
I am putting a 6.0 (LQ4) with a 6L85E into my’89 Trans Am GTA. I used to be a big stick-shift fan, but I’m getting older, and with a bad back, I’m finding that even shifting the manual trans in my ‘01 Jeep Wrangler is not as comfortable as it was 20 years ago. I do like to Autocross, and my ‘86 IROC-Z’s 700R4 has a manual valve body with a hurst dual-gate shifter.
I haven’t bought any engine management parts or TCM. I want to make sure I can go “full manual” with this 6L85 in my GTA. I want paddle shifters (which I will probably use with a MOMO steering wheel). I also want a “gear” indicator.

The specs:
6.0 (LQ4)
6L85E from 2018 2500 Silverado with 1,500 miles.
Twin turbo
BTR Stage 3 cam

I think that’s all the important stuff…
Any help would be greatly appreciated!
I can’t seem to find the info I’m looking for, anywhere on the internet. (I’m probably not looking in the right place. Wouldn’t be the first time!)
Thank you all!
Jason

 

Anyone? Surely I can’t be the first person that’s run into, or felt with this problem…
The only idea I’ve really had is to use a c-6 Vette ecm and harness, but there’s a few issues with that:
Boost-timing-retard via 3-bar MAP sensor.

Paddle shifter inputs: compatibility with factory input wires?

What shifter to use?

Shift indicator?
Any help at all’s greatly appreciated!
Thank you all, for reading!
-Jason

 

Have you tried googling it? I put in 6l80 paddle shifter and have a LOT on responses. Maybe I'm not understanding the question...

 

Yes, I did. I can find paddle shifters. The problem is that I can’t find the information on weather or not it’s all compatible. For instance, I found a harness on eBay that is supposedly made for the LS2 and 6l85e, but I can’t find any info on weather it has any “inputs” for paddle shifters. Also, it doesn’t say which shifter it’s compatible with…. I’m just really confused. I think I’m out of my “depth” here, which is an odd feeling for me. Maybe I’m overthinking it? I would like to find someone who has done this same swap. I know I’m not anywhere near the first one to want to do a “LS2,6l85e,paddle shifter, turbo swap. I just want to make sure I don’t go buying a bunch of parts I can’t use together. I tried messaging someone of these companies and have gotten zero responses. Holley wants you to buy it first, then they will answer your questions, apparently.
It’s all a bit much.

 

The TCM will be the place to look at to see if there are inputs for the shifters. My guess is just about every one does. I'm not running the same setup as you are, but I have a 4L70e with an MSD atomic TCM (https://documents.holley.com/2760.pdf) and a Lokar electronic shifter (https://www.lokar.com/assets/instruc...de-Shifter.pdf). It works fine for manually shifting the trans.

Looks like the Holley TCM has inputs for shifts - https://documents.holley.com/199r12431.pdf. Look at page 7. Once you find the TCM that can take momentary switch inputs for shifts, any paddle shifter should work. I did not do extensive research and don't have experience with the 6l80, so don't take my word as gospel. Just trying to help out.

 

I really appreciate it! That’s what I’m thinking. I’m probably going to have to go through the manual you found (or one like it, for the 6l80 platform). Seems to be the only way I’m going to be able to get the information. Thank you for the great advice!
It’s one of the last things I have to do, as far as parts go, anyway.