LSA with a 4L80e

[ryanlarue3]

Quick intro, I'm new to the tuning world and aspect really, slowly learning how all this works. This is also my first post ever and I'm getting used to the site so sorry if this is a double or a repeat

I am close to finishing a '69 camaro build that features a LSA with a 4L80e behind it. Reason for this combo? we didn't want to tear up the floors for a larger tunnel to use a 6L90. So a built 4L80e from B&M will do.

My main question is setting up the ECU and TCU to communicate with eachother. As far as I know, the only GM factory vehicle that came with a E67 ecu and T42 tcu were the V8 Colorado/Canyons (they didnt exactly come with a supercharger either). SO...

Do they automatically communicate and pick up eachothers signals via CANBUS? or do they need to know what they're communicating to; E67 needs to know its a 4 speed auto?

Like I said, forgive me as I am still learning this magic! Thanks for all the help!

[ScarabEpic22]

All TrailBlazers have the E67+T42 combo as well. If you want to use the E67 intercooler controls and LSA-specific stuff, not sure if/how to do that. I believe there are some aftermarket kits to convert a CTS-V 6L90E to 4L80E.

Getting a E67 + T42 running a 6.2 + 4L80E isn't too tough. Express Vans use the same TCM OS as the TrailBlazers for the same year. TrailBlazers have 60E/70Es, Vans 80E. Segment swap Trans+Trans Diag and done.

[ryanlarue3]

Thankfully I won't be using any of the ECU intercooler controls but I do know the OS is different due to well, having a supercharger and several different sensors and actuators. But that seems pretty straight forward. Thank you!

[ScarabEpic22]

If the OS' aren't compatible with each other (you'll need to figure that out on your own I'm afraid, even GM SPS doesn't know for certain) and you use SPS to change OS' (you can't with HPTuners), it may brick the ECM. What TCM OS is in the TCM, or what is the trans out of?

[68LSACamaro]

Hey guys. I?m new here, adding to this forum. I have an LSA crate motor(CTS-V) and a 4L80e in my 68 camaro. We cannot control the tranny through HP or the ecu. I?m not sure what to do here. The ECU looks to be out of a 2008 CTS-V. That?s what HP says. It appears this ecu can control a 6L but not 4L. The tranny is a jakes transmission from a 95-99 donor it appears.

Do I need an aftermarket tcu? Like TCI or something or is there a GM ecu that will work and control the supercharged motor and 4L?

[chrisxiv]

Bringing this thread back from the dead... I?m doing a LSA swap in a 69 Camaro with a 4L80e... customer has purchased all the PSI harness and has the same ecu/tcu combo mentioned in the OP...

Has anyone figured out a solution for this combo yet???


I know there have been guys on the TBSS boards that have done 80e swaps from the factory 4l70e. I believe this can be done w/o the need to segment swap(please correct me if I?m wrong), By adding a relay for the shift solenoid to reverse the polarity. I have not personally done this myself, so if anyone has any insight, please chime in.

[Shrek]

Bringing this thread back from the dead... I?m doing a LSA swap in a 69 Camaro with a 4L80e... customer has purchased all the PSI harness and has the same ecu/tcu combo mentioned in the OP...

Has anyone figured out a solution for this combo yet???


I know there have been guys on the TBSS boards that have done 80e swaps from the factory 4l70e. I believe this can be done w/o the need to segment swap(please correct me if I?m wrong), By adding a relay for the shift solenoid to reverse the polarity. I have not personally done this myself, so if anyone has any insight, please chime in.

PSI offers an "economy" based control system (wiring harness and computers) - with price being the driving factor.

PSI seem to lack the skill set (programming knowledge) to tackle non-OEM combinations - like your LSA 4L80 platform - which is something that was never offered by GM on a production vehicle.

Had you spent a few more dollars on the wiring harness purchase itself, you could have ended up with a wiring harness built for your specific platform, and computers (ECM and TCM) that were programmed for your specific platform. PSI does not offer this level of customization.

Trying to make the PSI system work with your specific platform will bring with it more than a few compromises. Better to have purchased the correct system (from a different company) at the outset.