I have a 58x Trailblazer SS LS2 that I have changed the cam & put LS3 heads & intake on. So it is basically an LS3 (minus .2 cubic inches). And I bought the GM LS2 controller kit 19166568. I need to purchase a throttle body yet & would prefer to use the LS3 piece. I have been reluctant to buy it because I hear it will not work with the LS2 PCM (factory).
On GM's website that describes their controller kits, it states that the 19201327 is the LS376/480 controller (LS3), and it is the same identical kit as the one I bought except the PCM is different. Same part number for everything else, including the wiring harness.
I know, I know, why didn't I buy the LS3 controller kit right? Because I bought it from an individual for about $400 less that I could get it anywhere else.
So, I am betting the PCM itself is the same for both kits, but programmed differently. Can the one I have be programmed to work with the LS3 throttle body instead of the LS2 piece?
Anywhere in my original post did I ask anything about having to switch the PCM for a cam and head swap? No.
I am putting it in an 86 Monte SS. I didnt have a harness, pedal, O2 sensors or MAF. So for about $50 more than the harness was going to cost me I discovered I can buy this kit. And it comes with all the parts I needed. I would rather use the LS3 throttle body as it is a better designed piece.
So I have done some searching through alot of OLD posts (like from 2008), on discussions on reprogramming the computers that come with the GM controller kits. Back then alot said it could not be done, then some tuner people said that they were working on changing their tuning software to accommodate this, but was still a pain in the rear. Has anyone actually done this or had it done?
What do people do who start with a crate ending, use the GM Controller kit and then change heads / cam? Are they stuck with that tune? Or do they have to ditch it all and go with a different harness / VCM so they can get it tuned?
Scot, the pcm can be re-programmed. As far as using the LS3 throttle body, I'm not sure. My AllData is too old or I could look up the schematics for you. Maybe someone with a newer version will look them up. You may have to sign up for AllDataDIY and look up the schematics for an LS3 car. If the wire colors and pinouts match what you already have in your harness, then you should be good to go.
__________________ 85 Monte Carlo SS, 5.3/4L60E Daily driver--traded
84 Monte Carlo SS, LS3 418, 248/254 615/595 with XER and XE lobes. AFR 225, 1 7/8 Hedman headers from BRP. 200-4R. 9" Ford, 3:50 gears.
I read many posts here, the crate comes with PCM would be easily and saveyour time..
Well then either you didn't read them very well or I am really confused: I have the crate engine controller kit WITH the PCM, but my engine is not a crate engine, it has had mods done so the crate engine tune won't be correct for my setup.