mta227

Hi,
I am a newbie/lurker who needs your wisdom concerning an eprom swap.

I want to swap the eprom from a 90 grand prix 3.1 VIN V 1227727 ECM into a 92 Grand Prix 3.1 VIN T 1227727 ECM. Do you have to swap the calpaks or memcals or whatever in addition to the eprom? Or is this just a direct chip swap? I would also like it to work with my OBD-I scanner for further tuning purposes.
I have not done this sort of thing before, so I am flying blind right now. If I do need addition parts to do this, would anyone know the part numbers for the 90 grand prix 3.1 vin V 1227727 ?

Thanks in advance for your time, as it will be appreciated immensely!

Grumpy

The 727 uses a memcal, meaning the eprom, calpak, and esc filter are all together.
Without having having all the particulars I'd wouldn't just for grins be swapping out memcals. By particulars I mean having a hac and reading thru it. It's a whole lot safer to be causious, then detonate a motor just trying something.
Either should be OBD I.

InTech

I don't know whether the esc in the memcal is the same or not. I'm a little lost as to why you would want to try this...are you just looking for a spare memcal??? Are you replacing computers and want to make sure the mem-cals can be plugged in???
-Carl

mta227

Well, actually I am trying to replicate a 1990 3.1 Turbo Grand Prix ECM (1227727), by using a slightly newer (eg. less rare) 1227727 from a normally aspirated 92 Grand Prix 3.1
The code for the Turbo Grand Prix 3.1 has been hacked thougly, and I have a copy of the bin. Just did not know if I needed something in addition to a newly burned eprom to make things work.

And thanks for your replies so far guys, I feel almost like a none newbie now, and I really do appreciate your help on this!

MTA

InTech

You should be able to plug and play as long as you are using a 2 bar bin AND a 2 bar map sensor. I would however verify that the pinouts are the same between the two apps as the software in the .bin can change the IO's. hth's
-Carl
p.s. The 7727 doesn't care what year 7727 .bin(eprom file) you put in it but the wiring harness might.

[This message has been edited by InTech (edited December 28, 2000).]

mta227

Thanks Intech,
That is kinda what I had thought was the case. The wiring was really not that bad. The TGP just uses a different EGR solenoid thereby freeing up some circuits to control the wastegate solenoid.
I did notice that the 92 harness had all of the injectors firing at once instead of in two batches of 3 *wierd*, but that was easy enough to fix also.
Things do get a little more complicated seeing that this whole control system is going on a 96 3100 VIN M engine with a turbo bolted to the exhast outlet. :0

Grumpy

I'm very sure the 7727 is a single output injector driver ecm. While there are typically 2 injector feeds into an ecm that is so not to overload the coper tracing on the Printed Circuit board. Anywho, using an ohm meter between the 2 injector pins will tell the truth, I'd sure like to see the hac <g>....

InTech

Me too on the hac thingy... I have always wanted to have a look at one of the 727 turbo .bins as well...
intech@writeme.com
Thanks
-Carl

mta227

I have a copy of the AUAF binary file. Most of the credit for the TGP 3.1 hack would be attributed to Mr. Kelly and the gmepro program I believe. If someone were interested I could easily be convinced into sending what I have via email. The current version of gmepro I have is only for evaluation and will not save to disk, but it is very nice for poking around the bin a bit.

MTA mta227@yahoo.com

P.S.
The comments on injector drivers has sparked my curiosity. According to my pinouts, the 7727 uses pins D3 for cyl 1,2,5 and D9 for cyl 2,4,6. Some schematics for the non-turbo 3.1's show the two circuits connected, but the TGP schematics show them going direct to the injector banks. I would like to verify this before I fire this thing up. :-)

Grumpy

Feel convinced <g>
nacelp@bright.net

The 730s, and 165s are all single driver ecms. The dual butterfly TBIs have two injector drivers, the only dual driver TPI ecm I know of is the 749. Then of course all the SEFI have one driver per injector.