matty b

Hey guys,
I have a customer that came in with a 7.4 swap in his 40 Buick. He bought a horrible kit from Ron Francis and installed it himself. Due to the instructions being horribly written he thought that a reflashed 99 pcm would work... it didnt. The pinouts are completely different between the pcm and the way the harness is setup . Also the way this setup is built it isnt that easy to move stuff around without completely reworking the thing. To the point the harness required a 96-97 pcm to work.

I got one out of an Astro van with a 5.7. Then I found a VIN for a C3500 with a 7.4 and 4l80e and flashed a new calibration onto it via Tech2. Since this is a hot rod it also needs to have emmision codes flashed out and have the gears programmed in.

I own HPTuners which I use regularly but I specialize in Gen3 and 4 swaps and didnt realize that HPT didnt support the 96-97 Vortec PCM. At this point I cant change these programming issues and although the motor runs quite nicely now it wont shift correctly and the speedo wont work right without the reprogramming, codes are secondary but should be turned off.

This leads me to my question, is there a tuning suite of some sort to flash this pcm? I dont want to mail it to anyone so thats off the table as they are overpriced. I know both HPT and EFILive dont support this pcm. Hopefully theres a reasonably priced option out there, if not Ill have the customer handle it himself and be done with it.

Hope theres some options out there.

KLUG'S SS

iTrader: (6)

Jet DST and you can pick it up for about $400

1Bear

iTrader: (1)

As mentioned, Jet DST will do it. You may also be able to locate some used TunerCat's software, which was bought by Jet and became the DST software. You can no longer buy TunerCat's new, it is only serviced to the original purchaser's before the buyout, but from what I understand, people say the original TunerCat's version is preferred and with it you can tune unlimited vehicles. While it's not as sophisticated as the newer software (EFI Live or HP Tuners), it is usable on vehicles all the way up to, but not including the GMT-900's.

The newer PCM's can be used with the older Vortec motors, but as you've seen, they will require the connectors to be re-pinned.

It sounds like you've got an interesting project on your hands, let us know how it turns out.

matty b

Thanks for the info, Ill look for a used setup as I wont use 4 credits in the next two years as the older swaps like that are old hat and more expensive than they are worth compared to LS swaps. If I cant Ill have the customer send it out himself.

I wouldnt have an issue repinning the connectors but the way they build this abortion of a wiring "kit" they make it next to impossible to do that. The way they set it up is there is a junction block with 4 terminal strips 30 terminals each. The computer plugs are pre wired to these strips in ALL THE SAME COLOR WIRE. so first Id have to literally ID each pin out at the plug but the move it at the terminal strip as well. All in all a HORRIBLE way of setting up an EFI harness.

This project isnt so much interesting as it is horribly built. The owner has written checks to a guy to build his car and the build is horrible front to back. It showed up at my shop to fix issues other shops did.

As of now the car runs fine, its just the computer tuning that needs to be handled. Beyond that the customer can have his car back ASAP lol