Hey guys. Finally finished putting on my Big16G turbo, but it is not as quick as my T-25. I really have no idea what is wrong. I have the manual boost controller in and almost turned all the way Clockwise and nothing. It doesnt even spool until like 4,500 maybe even 5,000 rpm. Anyone have an idea? Please help.

 

well you should expect some lag with it because the t25's are much smaller and they spool alot faster than most turbo's but that does seem a bit too much lag. I dont really see a MBC being the issue. Sounds like something may not be hooked up tight enough or something

 

yeah, do you think it could be the fuel system at all? I have the stock fuel system.

But I was also think about the manual boost controller. To tell you the truth I am not sure if I hooked it up. I used a t-fitting off the BOV line and another from the wastegate line. Is that correct? I was a little confused on the instructions.

I am pretty sure everything is on right. When I first took it out on a test drive it spooled a lot quicker than now, but a little slower than the t-25. Then I floored it again, and then I heard a pop. After that, it just started spooling alot later, like now around 4,500 to 5,000. Please help.

 

I took it out for another spin and the turbo seems like it was to spool around where my stock t-25 turbo did, but it seems like I have a parachute holding me back from letting it do its thing. I can hear my Big16G turbo spool, its so loud, but it doesnt have as much power as the t-25 did (at least now it doesnt seem like it)

Oh yeah, I also adjusted the MBC and I turned it all the way up (as in Clockwise) to see if I had too low and I didnt hit "fuel cut" at all. And I have the MBC turned up almost all the way up. Seems like something is wrong there too.

 

Where did you get the turbo? Maybe you got one of those nock off ones.

 

^^^ that or you have an exaust leek right before the turbo. after you install anyhting that involves exaust work your suppose to run the car for a while then go back while the bolts are hot and tighten everything again because when the get hot they expand and become loose.

 

Thanks guys. I am going to check it out today again. But I also noticed that I have my manual boost controller connected wrong too.

By the way SEBBA, look under the Nitrous, Super Chargers, & Turbos topic. I found something for you, that you were looking for awhile back.

 

Anyone know what else it can be? I checked out the exhuast system, the turbo manifold, intercooler piping and everything seems fine. Please help. Anyone know what else it can be? Could a vaccum line cause this problem?

 

What you described sounds very similar to what I'm going through. I don't know if this helps but I bought my 98 GS-T 2 months ago, the guy who had it before me put on a bigger turbo, and nothing else, and since i've had the car it stops acclerating at full boost and rpms wont go up at all, like its just not getting the fuel. It doesn't feel anywhere near 200 horsepower. I bought a 190lph fuel pump to try to fix the problem, I called a dyno and was told I needed a Afc2 to make 190lph pump more fuel. Going to order a afc2 today, hopefully thats fixes the problem.

The way the person I talked to put it, "when you add a bigger turbo, the computer doesn't recognize it and/or isn't able to pump enough fuel to compensate for the increased air."

 

Did you fix this and what did you do to fix it. You dont need any type of t-fitting to install a MBC. One end goes where you have it now (on the wastegate). And the other goes on the turbo. no fitting necessary.