OBD1 to OBD2

[Tonglebeak]

How difficult would it be to swap an OBD2 ecm into my 88? IIRC '96 is the first year the OBD2 systems were used, correct? What all would be involved?

[notsoslimshady76]

It's very difficult. This guy here covers the basics:

http://gmwbody.com/viewtopic.php?t=835

[Tuddi]

It's very difficult. This guy here covers the basics:

http://gmwbody.com/viewtopic.php?t=835

Whew... that guy must be crazy! Reading most of the 6 pages it is clear that rather than doing all he's doing, time would be better spent in a sauna :)

Must be young and eager to "do the impossible". I wouldn't do such a thing even if I was getting bored to death. .... probably getting too old for that kind of thing. In my teens it was a different story... I'd spend all my time on my SUV's and love every second of it... even the moments when things just went bad all the time. Not any longer .... fortunately.

[Jr's3800]

Yeah its a bit rough going from OBD1 to OBD2...

I have a friend doing this as he has a an L27 Tuned Port 3800 with all of the Supercharged Components... Instead of using the Gen 2 M62 Eaton he has put together an M62 Gen 3 with the coated rotors which gives it more efficiency in the amount of air it can move...

At current he is working out the wiring harness and has installed some of the new items on the engine.. We are doing this as it will give him better ability to tune the car and he'll be abale to get the program and do this with his Lappy Top Puter...

Also later on down the road it will simplify a series II L67 and 4T65-E swap..

Getting it all figured out is the real headache:)

[Zaloryan]

What benefits would you get from the switch?

[notsoslimshady76]

theres a lot more control over the engine. You can tune better since it has more sensors and more advanced computers. Better mileage too I'd imagine

[Jr's3800]

Ok lets look at it this way...

I have a 1995 Bonneville SE with the Series II L36 NA ....

Its full on OBD1 with OBD1 protocol... But it uses the OBDII codes and OBDII 16 Pin connector..

the PCM used for this car and many of the 94-95 3800's was a tad bit funky Yet it was a more powerful PCM... Yet to be able to tune it you have to have someone that can flash the EPROM for it...

Now I went to a Front Plog ( Performance Log, Its really a decent Tubular Exhaust Manifold, if it doesn't crack ).... In doing this the front bank of cylinders was now flowing more... So in order to keep the front cylinder from ever becoming lean I needed to skew the injectors to flow 2% more to the front.... But on the 95's EPROM this can't be done... So i ended up with a flow matched set for the front that flows 2% greater than the rear... This engine and PCM does use 2 knock sensors and will show and log Misfires and live misfire data.. Supposedly there is no Torque management in the 95 PCM, but in looking at the files there are tables for it and I am thinking that may be gears towards the traction control as the PCM and EBTCM would communicate with each other in an effort to curb wheel spin when the Traction Control was turned on... The PCM would actually kill off timing... In this PCM there is a 1-2 upshift Maximum Torque desired.... 2-3 and 3-4 do also... For an OBD1 PCM it does have quite a bit going on...

When you get to OBDII.... things get a lot more complicated..

Say you bought a 1997,98,99 GP GTP... You would most likely find that the torque management would most likely be set at Maximum torque of 300 Ft Lbs... So even bone stock you are being help back... There is even a field for abuse mode...LMAO.... From a tuneability standpoint you can make a lot of changes with the OBD2 PCM... Everything from timing, to shift point, to rev limiter to speed limiter to fuel cutoff.... And the OBD2 uses Boost referencing.... The list just goes on and on... also on this PCM you can simply tell it to flow more on the front bank if needed... You can raise the line pressure on the 4T65-E... Its really pretty neat..

and I get just as much mileage from my 95's strange computer as the OBD2 system.. I generally do 29-32 Mpg with a fully loaded Bonneville AC on runing 75-80mph all day long... I always have.... Might be one of the reasons I just can't let the car go...lol

Lets just say it was really cool to sit with my buddy and see all of the fields and changed that can be made with the PCM... Its down right amazing... And getting more and more complicated... Try driving a Drive By Wire car sometime.... Its freaky, take a little getting used to... And the system will do everything it can to protect its components...lol

[Tuddi]

Better mileage too I'd imagine


Absolutely.

I just checked and you are right. The first year or so will be literally free for you on the gasoline account if you do the swap:


Posted: Tue May 29, 2007 5:20 pm Post subject: OBD version 2.0 swap (56K beware)
I am doing an OBD2 swap. I started it today.


Posted: Sat Jan 05, 2008 11:17 pm
I really don't know.

I am hooking it all upp, and carefully researching everything I do. The people that I have talked too say it will not work, but none of them have actually tried it. If I have to go to a newer setup, I will.

I would rather get another car and have something to move around in. :D

[SexySilhouette]

Whew... that guy must be crazy!

Yeah, he's crazy...He's also a very good friend of mine.:)

[CieraSL92]

Not worth it.

[bigjoe1015]

Ok lets look at it this way...

I have a 1995 Bonneville SE with the Series II L36 NA ....

Its full on OBD1 with OBD1 protocol... But it uses the OBDII codes and OBDII 16 Pin connector..

the PCM used for this car and many of the 94-95 3800's was a tad bit funky Yet it was a more powerful PCM... Yet to be able to tune it you have to have someone that can flash the EPROM for it...

Now I went to a Front Plog ( Performance Log, Its really a decent Tubular Exhaust Manifold, if it doesn't crack ).... In doing this the front bank of cylinders was now flowing more... So in order to keep the front cylinder from ever becoming lean I needed to skew the injectors to flow 2% more to the front.... But on the 95's EPROM this can't be done... So i ended up with a flow matched set for the front that flows 2% greater than the rear... This engine and PCM does use 2 knock sensors and will show and log Misfires and live misfire data.. Supposedly there is no Torque management in the 95 PCM, but in looking at the files there are tables for it and I am thinking that may be gears towards the traction control as the PCM and EBTCM would communicate with each other in an effort to curb wheel spin when the Traction Control was turned on... The PCM would actually kill off timing... In this PCM there is a 1-2 upshift Maximum Torque desired.... 2-3 and 3-4 do also... For an OBD1 PCM it does have quite a bit going on...

When you get to OBDII.... things get a lot more complicated..

Say you bought a 1997,98,99 GP GTP... You would most likely find that the torque management would most likely be set at Maximum torque of 300 Ft Lbs... So even bone stock you are being help back... There is even a field for abuse mode...LMAO.... From a tuneability standpoint you can make a lot of changes with the OBD2 PCM... Everything from timing, to shift point, to rev limiter to speed limiter to fuel cutoff.... And the OBD2 uses Boost referencing.... The list just goes on and on... also on this PCM you can simply tell it to flow more on the front bank if needed... You can raise the line pressure on the 4T65-E... Its really pretty neat..

and I get just as much mileage from my 95's strange computer as the OBD2 system.. I generally do 29-32 Mpg with a fully loaded Bonneville AC on runing 75-80mph all day long... I always have.... Might be one of the reasons I just can't let the car go...lol

Lets just say it was really cool to sit with my buddy and see all of the fields and changed that can be made with the PCM... Its down right amazing... And getting more and more complicated... Try driving a Drive By Wire car sometime.... Its freaky, take a little getting used to... And the system will do everything it can to protect its components...lol

What you're describing is OBD 1.5 If you scroll down this page, they describe it.

http://en.wikipedia.org/wiki/On-board_diagnostics#OBD_1.5

[86euro]

Weren't the Ciera's still OBD 1.5 in '96 anyway?

[Jr's3800]

What you're describing is OBD 1.5 If you scroll down this page, they describe it.

http://en.wikipedia.org/wiki/On-board_diagnostics#OBD_1.5

I was trying to show a few of the differences and how much more complicated the systems became..