Tuning OBD1.5 for boost

[Azrael]

First time poster, Long time reader.

I decided a few days ago to seriously look into getting RSM's supercharger kit for a 3x00 V6 in my 95 grand am. Since this car has OBD1.5 I know my tuning options are extremely limited especially since I need it to work the 4t60e too. The only idea I've had so far is to use a piggyback A/F controller but I realise that the stock ECU can only be tricked so much. I could also use the FFP underdrive pulley to slightly lower the output of the SC if necessary (~6psi. of boost is still better than vacuum).

Basically I'm here in hopes some of you might have other, possibly better ideas.

One other 95 owner has had a GM supercharger successfully installed on a 2.3L Q4 with a manual tranny. I'm not sure how much of a difference his ECU is from mine but he seems to be doing fine (albeit a little rich) with just an Apexi S-AFC 2 for fuel control.

[bszopi]

RE: Tuning OBD1.5 for boost

Check out www.perfectpower.com I think they have probably some of the better piggyback systems out there.

[Azrael]

Thanks! Options are always good to have. I've got a good baseline on what to do now: Headers -> 3400swap -> SC. I've found plenty of good basic tuning info over the net but I'll definitely have it dyno-tuned once everything is in.

[timg]

http://www.splitsec.com also has some good piggyback systems. Vortech uses Split Second for quite a few of their supercharger kits. I'm running one on my Z34. Their FTC should be able to do ignition timing modification and MAP (or MAF) sensor modification. I believe some of their boxes are also available with additional external inputs.

GReddy e-Manage may also work, though I don't know if it has a compatable crank trigger setup for ignition modification.

Tim

[Azrael]

With aftermarket fuel control I need to know which wires on the ECU to tap into. Does anyone know where to find the wiring/pin schematic for my ECU? The one for 3100's listed under the "In Depth > Computer" section doesn't seem to apply since it shows an input for a MAF sensor which my car doesn't have.

Also is ignition retarding even necessary for low boost?

Sorry for the simple questions but that's why I'm taking a year to do this.

[timg]

For 7 psi, you should be relatively safe without retarding ignition timing. If you break 7 psi, you will definitely want it. I'm really glad to see someone taking their time and planning!

Tim

[Rook]

*bump*

i also am planning on a 3400 swap + turbo setup on my 95 grandam obd1.5

so would i basically need an air/fuel controller and ignition controller if im gonna run 9-12psi?

anyone tried a standalone? im no tuning expert by any means, but would Greddy eManage or AEM EMS work? i know some shops in my area that could tune either of those for me with a dyno.

but would say apexi s-afc work ok? or should i go with some other a/f controller?

[Azrael]

I had done a crazy amount of research after I made this thread. In the end I decided to go with an OBDII swap since just about everyone is capable of working with it. Also decided against RSM's supercharger and go with DPP's turbo kit for the considerably better power to price ratio.

One option I seriously considered was Perfect Power's SMT6/7 piggyback system.

[timg]

Haltech also has a good piggyback system.

As far as tuning, PCM tuning and piggyback tuning are probably equally difficult. IMO, a good standalone is easier to tune than either a piggyback or stock PCM.

Tim

[Manitcor]

A couple people including myself have managed to change out the harness and PCM with a 96 ODBII harness and PCM, once you figure out all the wiring (normally only a couple connectors a couple sensors and change a couple pins on the body connector) you can do the actuall swap in about a day.

You options are much wider after that.

[gboogie99]

where can i find the info on how to swap up to OBDII? I've got a 95 Ciera that I'm about to turbo and dont want to have a whole bunch of custom chips

[WhiteRaider]

The 95 Ciera ECM is programmable with Tunercat. I have the definition file for it, but don't know how easily you could tune for boost...

[Manitcor]

where can i find the info on how to swap up to OBDII? I've got a 95 Ciera that I'm about to turbo and dont want to have a whole bunch of custom chips

There is no posted article yet, I really need to sit down and do one, Im hoping to have some downtime over thanks giving to do this.

Ive also learned a couple things since I did mine that would have me do things a bit different if done again. First thing is if your car has a 96 or 97 model year this will be much easier. If not it can still be done but you have th extra issues of dealing with not only cross year but cross model idosyncarises.

Parts:
a complete harness (including injector harness)and PCM for your model/trim car from 96 or 97
96+ temp sensor
96+ Knock sensor
96+ shift position sensor (for t60 folks)
96+ egr valve
96+ PCM box with air intake snout

Since your doing a turbo I would reccomend larger injectors, you can either modify your injector harness and step up to GA injectors or you can get large Multec style injectors (I think they are avaible up to 45#)

Theres some splicing required and some pins that need to be moved on the body connector (very easy) if you are prepared ahead of time and have all your parts the actual upgrade can be done in a weekend.

I personally went to a 96PCM HOWEVER i have found that the 97 PCM has even more tuning options than the 96 and the 97 harness is still very close to the 95 harness for most cars (98/99 is a no-no they changes alot in those years). But there are differences in the 97 and I havent had time to look it up myself but I will as i plan to modify my 96 harness to accept a 97 PCM when I get the time.

I can give you assistance technically, it may help if you have a digital camera.

[gboogie99]

i wouldnt know where to begin with a definition file. How hard is the swap to a 96 OBDII and how long does it take? Could it be done in a day?

[gboogie99]

anyone?