3.4 DOHC turbo

[timg]

Thanks for the comments. I'm hoping to run 10-12 psi everyday on the motor as it is now. I'd like to run more, but have a LOT of work to do first... Good luck with the 15 psi. I will love to see how that turns out!

I get around 20 mpg on the highway. It's not far off from stock. Around town can be pretty dismal though. It really depends on how heavy your right foot is. If you're getting on it all the time, gas mileage is noticably worse. If you take it easy, gas mileage is roughly the same.

I am running a stock computer, but have a split second FTC1 that can take care of ignition timing and fueling installed (but I really need to tune it). 42.5 lb injectors are lost somewhere in UPS's system and an AEM wideband gauge is sitting at home. I also have a 96 ECU and wiring harness...

Tim

[Kohburn]

woow now thats motivating... almost 270whp at 7psi would = a happy me in the fiero

[SappySE107]

If there is enough interest near me, I would love to tune a turbo 3.4 DOHC. I could probably do the MAF a little easier though I still need to mess with shift points and with boost, who knows on drivability. I guess tim would know how it runs with mostly stock programming other than the add on. Brian had a MAP setup he was working on but I haven't messed with boost so either way its going to be a little different than what im used to.

If needed, ill turbo my car and tune it, but that won't come till I can afford such a project. Also its a 5 speed and MAP so that will be interesting (possibly the most difficult setup to tune with the stock ECM, i dunno). The 94-95 setup is really nice, and a 96 setup would probably offer the greatest advantage in programming for stock. Im wondering how hard it would be to make the MAF chip work as solid SFI so a MAF swap to the 91-93 would be possible. I have a feeling the tranny will cause some problems there as well. Im not a programmer, I just tune. I believe the guy on gmtuners can edit the executable portion of the code. Those guys can do some amazing stuff.

I have some other questions but ill just use PM cause this is getting really long. Has my interest though, and i haven't checked the links yet.

[93gtpdohc]

well, i'm useing the TGP.bin, and it's not really hard to tune with the right tools, and i also have a 5 spd, the only down side is that it doesn;t take much to max out the stock clutch, which i am still useing until i afford a stage 3 one,

[Fierobsessed]

Since your car is stick, you don't need to use the 16194396 anymore. The 1227727 is pretty much a plug and play replacment, and it supports the $8F code. Come to think of it, I'm told the 16194396 is also capable of supporting the $8F code. Could be an easy way out, but will have no benefit to the 4T60-E owners.

[pontiacjeff]

I'm trying to decide which ecm to use ofr my project. I have a 90TGP, a 94-95GTP and the 96GTP computers to choose from. I can easily get the $8F calibration for GMPCM (what I tune with). I also have the DHP Powertuner (it tunes real nice), so I could use the orginal 96OBDII computer and harness. I have the 94-95 harness hooked up to it right now, modified for the 96 engine (coil mounting, etc.)

What are some opinions? Which should I use?

[pontiacjeff]

Oh, 96 3.4DOHC with 4T60E, turbo'd, 50# injectors, LS1 MAF.

[SappySE107]

If you can do OBD2, I would go that route. SFI is also something that may be desired with large injectors for idle purposes. 94-95 would be the 2nd option id go for.

Using the TGP bin might make some things easier but im not sure how it stacks up in the end to the 91-93 programming modified to control boost.

[Froggx]

The two biggest limitations I have found with working with the TGP code for my project are no SFI and you are theoretically limited to 14.7 psi of boost. If you have 50# injectors I would recommend keeping your distance from the TGP code as many people cannot figure out how to get lowly 36# injectors to idle correctly. If you were to work within this limitations though it is a very nice setup.

[LQ1]

50# injectors................your outta your mind. I figure, using the FMU I have, and stock injectors, ill be putting the injectors at about 90% duty cycle. So ill obviously have to go bigger, im thinking GTP injectors but I forget what they are rated at. 50#'s IS HUGE, and would require some serious tuning for normal driving. S/C stangs running 14psi can run 11s on 30# injectors. Just requires raising the fuel pressure, which is where the FMU comes in handy. Tune bigger injectors, like 30-36# for normal driving, and let the FMU take care of the racing.



EDIT: my friend just S/C his 5.0 and is running 38# injectors at 27-30psi and its got waaaay too much fuel. Running an 8lb pulley and cobra spark plugs.

[Froggx]

38# injectors on an 8 cyl motor and 50# injectors in a 6 cyl motor (assuming 1 injector per cylinder) have almost the same theoretical maximum amount of fuel they can deliver. Is he getting too much fuel because of a poor tune or just because he cannot get them to open and close fast enough?