Why does my Bone stock 96 3100 GP seem faster than my modded 95 GP 3100

[Rhedalert]

I wouldn't be too surprised with the tuning being the cause. With OBD I and II, GM knew they'd be using them for several years each. With OBD 1.5 it was only used for one, maybe two years. Which ones do you think they spent more time/money on?

OBD1 is just as bad as OBD 1.5 as far as GM is concerned. OBD1 is just able to be tuned. Really it's the speed density system, it has difficulty adjusting for any modifications. MAF setups seem to work a lot better, though it's not going to be perfect either.

I'll be posting everything about what I did on my site. When I do I'll let you all know!

[blackbombshell95]

OBD1 is just as bad as OBD 1.5 as far as GM is concerned. OBD1 is just able to be tuned. Really it's the speed density system, it has difficulty adjusting for any modifications. MAF setups seem to work a lot better, though it's not going to be perfect either.

I'll be posting everything about what I did on my site. When I do I'll let you all know!

Let me be the first to know

[Manitcor]

Defintaly go for the ODBII swap, it takes some time to get all the right parts together but once you do you can do most of the prep work in your living room with the new harness. Once your ready you can typically install the harenss in an afternoon.

It is like night and day just going to a stock ODBII PCM. I picked up the full powertuner setup and with a 1.5 tune you can really take advantage of your mods.

If you can go for a 97 setup, I know at least on the Montes and Luminas there are some differences between 97 and 96. Ive tried using a 97 PCM on my 96 harness without any luck, granted I only tried once and J/Y pcms can be hit or miss.

Good luck.

[Rhedalert]

That's weird. I compared my OBD2 harness I pulled from a '97 Lumina, it's the exact same as a '96 Harness as shown in my GM book. All pinouts etc are the same. The only thing different is a mid-year change in '96 of a fuse in the #1 electrical center, but I think it's just the labeling (one says TCC the other says CRUISE) so maybe early '96 was different? Either way, been driving on a '96 PCM with a '97 harness and it's been good.
Also what did you do with that secondary EVAP solenoid, did you use it? I forgot to grab it at the junkyard. So far the PCM hasn't cared.
Overall it really is a night and day difference though.

[Manitcor]

The PCM hasnt seemed to care about the solenoid. I did notice that the pinouts from the PCM were the same for the 2 years though the PCMs themselvs are markedly different. I spoke withh charles and he confirmed you have more tuning options with a 97 PCM.

When I went to install the harness I found that the differences mainly lie in the body connector. I had to move some pins around and run an addational power line from the fuse box for the blower motor. Its likely I had a bad 97 PCM or perhaps I messed somethhing up in my wiring. I havent gotten around to trying another 97 PCM yet.

After upgrading to ODBII I noticed improved performance and better gasmileage and then once I got the PowerTuner and was able to tune to my mods all of a sudden I was embarrasing 3800s left and right.

[blackbombshell95]

So only a PCM and wiring harness from a 1997 w-body with a 3100

[blackbombshell95]

Ed morad has a 2002 3.1 uncut wiring harness w/ecu. Would that work?

[Rhedalert]

not as far as I can tell, an '02 has a 4T65e tranny while you have a 4T60e. There's other differences I'm sure.

Yeah, the body connector (C100) was definetly an issue, but I think I only actually moved two wires, and the biggest change I had to do was add another (10 gage?) power wire to the connector. '96+ the power wire is split on the interior side and combined to 1 by the time it hit C100, while '95 never combines. Not a real big deal but hair-raising anxiety just before I hooked the battery back up and turned the key.

Are you sure a '96 PCM is different than a '97 PCM as far as tuning? I thought the various sites listed that, as '97 was when the 4T65e came about in various platforms, so you can mess with shift firmness (line pressure) but is there more to it?

Right now my MIL came on and has been on, but I can't scan it just yet. I have to install the 16-pin diag port sometime this week

[Rhedalert]

Oh and to add, I'm not concerned with (at least stock) 3800's. I was able to take them just enough to beat them with my old setup. NOW it should be a roast

[Manitcor]

not as far as I can tell, an '02 has a 4T65e tranny while you have a 4T60e. There's other differences I'm sure.

Yeah, the body connector (C100) was definetly an issue, but I think I only actually moved two wires, and the biggest change I had to do was add another (10 gage?) power wire to the connector. '96+ the power wire is split on the interior side and combined to 1 by the time it hit C100, while '95 never combines. Not a real big deal but hair-raising anxiety just before I hooked the battery back up and turned the key.

Are you sure a '96 PCM is different than a '97 PCM as far as tuning? I thought the various sites listed that, as '97 was when the 4T65e came about in various platforms, so you can mess with shift firmness (line pressure) but is there more to it?

Right now my MIL came on and has been on, but I can't scan it just yet. I have to install the 16-pin diag port sometime this week

Yeah thats exactly what I had todo, as far as theh 97+ goes, yeah the t65 came in alot of cars 97+ except montes and luminas with the 3100, they had t60s all the way to 99 only the Z34s got the t65 97+. The PCMs are markedly different, im not sure the excat things you can do more with the 97 PCM but as I heard you ave more options when tuning the 97PCM. I think I just need to find another 97 PCM and give it another go.

[blackbombshell95]

A 1997 PCM/harness from a lumina or a monte carlo. The 97 Gp 3100's had a 4t65e?

[Azrael]

Grand Ams had the 3100/4T60E combo untill 98. The ECU part# was different between 97 and 98 but I don't know what changed between the two.

[bszopi]

So... I guess I need to look into this. My probably is to what extend I want to do it. I want to get a 3400 PCM since I have the 3400 now. I would like to do a 65E swap when my 60E finally dies, so I'd have to get a 65E capable PCM as well. This would mean a 99+ PCM. But, this would also mean I would most likely have to upgrade the BCM as well as a bunch of other stuff I would suspect. I guess I'll have to find a possible match and start doing some researching, and then start looking for a donor.

So did the Monte's ever get a 3400/65E combo? Or was it the Impalas?

[Rhedalert]

A 1997 PCM/harness from a lumina or a monte carlo. The 97 Gp 3100's had a 4t65e?

a '97 GP SE w/ 3100 and 3800 got the 4T60e. '98 it changed to the 65E

[blackbombshell95]

a '97 GP SE w/ 3100 and 3800 got the 4T60e. '98 it changed to the 65E

Cool. I'll start looking around for a 97 wbody 3100 ecu/harness. Ed morad only has a 02 3100 harness/computer