Moving from 1227747 What is the best TBI ECM to use?

[trlrider]

Thanks guys, appreciate all the info and advice.

Were the 7427 only available in '94-95 trucks/vans? Are there any tell tales signs for the vehicle to indicate it has this ECM as opposed to other ECMs from the same dates? Saves pulling a lot of glove boxes off the hinges. i.e. VIN codes or glove box VIN stickers.

Also, while I have your ear, in the 7747, does the BLM data get deleted when the battery is disconnected? How is it stored in the ECM? I have been removing the battery cable every time I change the PROM tune, not sure if that is detrimental or not. I suppose I could be extra careful putting in the chip and leave the battery connected if need be.

Thanks!

My 1993 Suburban at some time in it's life had a dealer replaced ECM, and it was a '7427, so I lucked out when I bought it, swapped in earlier crate engine and started tuning.

[kilohertz]

My 1993 Suburban at some time in it's life had a dealer replaced ECM, and it was a '7427, so I lucked out when I bought it, swapped in earlier crate engine and started tuning.

I lucked out too. The truck I stripped was built 10/95, which technically is a '96. I was very happy to find the 7427 and red/blue harness. Stripping of all the old loom tomorrow and get it ready for install this summer...bloody snow.

Cheers

[tayto]

the vin is more accurate for figuring out year vs the manufatured date

[trlrider]

the vin is more accurate for figuring out year vs the manufatured date

eh? yes, the vin does tell what MODEL Year it was built for, it does not tell the manufacture date though normal decoding.
What does that have to do with what ECM it has?
I have a 1993 Model year that had a dealer replaced ECM, that just so happened to be a '7427. I even found a late model year '92 with a '7427 at the salvage yard.
GM does supersede ECM's for various reasons, so it is not all that unusual to find one in anything from '92 to early '96 depending on the vehicle model.

[kilohertz]

This is too funny not to share...

I stripped down the new harness today and removed the superfluous wires, it's amazing how many wires are not needed. The whole harness was covered in oil so I washed it and wiped it all off, it should work just great in the '68 Firebird. When I was finished I sat down next to the workbench and had a beer, and casually looked over at the distributor cap and distributor that I got from the same truck....and noticed it only had 6 posts. WTF, I thought this was a V8 truck. Too funny, turns out it was a 4.3 C-1500 so I now have a good distributor for a transplant into my '66 Corvair, which I am also planning on a TBI install with dual small TBI bodies...one day. I hate getting old.

I'll read the MEMCAL in the morning and if it's something new, post it in the appropriate thread.

Cheers

[tayto]

eh? yes, the vin does tell what MODEL Year it was built for, it does not tell the manufacture date though normal decoding.
What does that have to do with what ECM it has?
I have a 1993 Model year that had a dealer replaced ECM, that just so happened to be a '7427. I even found a late model year '92 with a '7427 at the salvage yard.
GM does supersede ECM's for various reasons, so it is not all that unusual to find one in anything from '92 to early '96 depending on the vehicle model.

'96 is when the c/k trucks went to vortec, completely different induction system, harness and PCM. 1993 I could see getting a 7427 considering it used the same connectors. i am having a hard time believing the '92 was "dealer swapped" to a 7427. surely there would be some gm literature for techs to back this up. kinda thinking it's more likely someone swapped a door from a 92. did you verify the vin in the door matched the VIN on the dash? While on this topic, i have read that mexico ran TBI up until 1998 or maybe even 2000. being in texas it could be very likely you have these truc,. But being in canada very unlikely.

Also, not sure how much you've done in the automotive industry, but VIN number is by far asked for more to identify a vehicle than the date in the door. Have you ever gone to the ANY dealer for parts before? they usually want your VIN number.