I have a 92 Z28 with the 350 TPI and Auto. I built a custom Turbo system, now I tring to tune it. Only changes I made to the stock program was to change to 30 lb injectors. Throttle Response became very crisp, and car idled smooth. But as soon as the car see's Boost it Bogs. Before the injector change car run very rich at idle, But would Boost with No problem and it screamed. I'm useing the orginial MAP sensor.


Ray

 

Are you using an FMU?

If not, you could go that route... OR - I'd recommend running either A) '749 ecu swap or B) $58 mask on your '730 ECU. You'll want a boost-reading setup in there, for ease of use.

Details on the turbo setup!!! Size, how you made it, etc!

 

check out " My Tubro Project ", I have a bunch of Pictures in there.

Where/How do I load that $58 code? I'm using Tuner Pro RT. What file do I install it in?

Ray

 

Did you have injectors in that were larger than 30lb before? I'm confused why it was running rich at idle and ran fine on boost before the injector swap.

I use a Votech Super FMU and 24lb injectors in my TT IROC, and A/F ratio and drivability is good up to 6psi (I haven't run higher than that except for a few seconds when playing with the wastegates). I run the stock PROM, and blow through the stock MAF sensor. An MSD BTM and 6AL control spark. I know its not ideal, but it works. I would love to start custom tuning, and run a '749 ECM, but time hasen't permitted it yet.

 

No I had the 24 lb injetors, then I put the 30's in there and lowered the fuel pressure, but the PCM thought it still had the 24's in there so it was throwing alot of fuel at it. then when it came on boost the A/F came more in line.

I then later programmed in the 30's. But this programming stuff is alittle over my head. I just order a Cartech/ Begi Billet fmu, until I get a better handle on the programming thing.

Do you know anything about the Cartech/ Begi Billet fmu? I run 9 psi of Intercooled Boost.

Ray

 

I have had issues with the stock style ECM programming thing too, like different scan results for the same temperature, load and RPM parameters makes it hard to figure which way to move the fuel. Also if you choose to run a bigger blower cam, the vacuum at idle becomes tuning issue as well. I don't really know what to do either

 

I have that FMU in my turbo Z24 and it works very well. It's much easier to tune than the Vortec FMU in my 89 IROC. Make sure you check your max pump output pressure before you install it (the directions are very good and will explain that for you). No FMU can force the rail pressure higher than the pump is capable of producing!

 

thats why blower/turbo kits come with a in-line. Even the in-tank vortech blower pumps cant produce the kind of volume and pressure with an FMU that they can when used together with the supplied in-line on those kits. Bottom line, 99.9% of the time an in line is needed too.

 

I have the Zex Inline Pump. It says it is rated up to 650 HP. Anyone ever use one of these?


Ray

 

post a picture of it and we will try to tell you who really made it

 

I went and pulled the foam sleave off of the pump and it turns out that the pump is a "Walbro GSL 392".


Ray

 

walbro is #1

 

Who makes my Vortec T-Rex 50/70?? I am looking for a quieter pump- anyone have suggestions?

 

Im pretty sure it is also a walbro, the in-lines sold by vortech and ATI are walbro. also the BBK in line and in tanks and holley in tanks.