I keep getting a weird stalling when i see more than 15psi of boost. It seems to be load dependant. I am wondering if this is detonation or not?? I tried adjusting out my fuel pressure regulator, but it stills does it? I think i have those damn autothority chips. If anyone can ask me a few questions and let me know if this is a really bad detonation or just flooding the motor,that would be great.

 

Detonation sounds like a couple kernels of popcorn shaken in an empty coffee can. Do you hear that? It's about that loud too, so you really have to listen. If it's more obvious than that, you've got serious problems.

Most likely it's one of two things: overboost-protection or intake-hose leaks.

If overboost-protection kicks in, the fuel is shut off and the car takes a MAJOR surge; make sure you're wearing your seat belts. As boost-pressure drops, you can then get on the gas again, but it's very abrupt.

If it's intake-hoses, that makes more sense as they cause a more gradual stumble. That's because there's a critical boost level that causes the loose hose-clamps to open up venting boost, but below that level, the car runs fine. I'd check every single hose and clamp leading out of the turbo. Feel under the hose that comes out of the turbo as well because it can split on the bottom side without you seeing anything obvious. It actually would be a good idea to take ALL of those hoses off, clean the mating surfaces with acetone to remove oil, then reassemble making sure the hose-clamps are tight.

 

Thanks a ton for the info! From what you described, it definately sounds most likely to be the hoses. It is somewhat abrupt, but not like i hit a wall. Just a stumble...but if i back off the throttle I can smooth it right through to redline. Weird huh? And i definately dont hear any popcorn kernals knocking around, so thats a good thing. The first hose from the turbo to the intercooler pipe looks a little cracked, but on tight. I think i'll just disassemble it all and see what happens. BTW danno, im gonna get a fuel pressure tester for my fuel regulator. What psi should i run it at to get it to 12.5-1 at the leanest?

 

Let me know what you find...
I just brought it up to 16-17 and I'm getting the same thing...

it MAY be knock, I hear no such noise but I still think it may be knock...doesn't make sense at this boost level though...to feel it this much... + im running 94 octane from sunoco...

Guess I'll check all the hoses again...

 

At 16psi the car pulls smoothly..I tightened up some hose clamps at the same time I turned it down from 17 though.

Oh well, the wonderful interesting life of a turbo car

 

I've noticed the same thing about it being boost dependant. Nothing at 14psi or so, but at a lower rpm where i have more load i can see up to 16psi. Its at about 16psi that it does it. Where can I get a whole new set of purocil (or whatever is best) so I can re-do all of the hoses? I also was thinking of just doing a J-pipe intake to Kind of clear up the front of the engine bay. Will speedforce racing make a J-pipe for my car with all hoses? How much if anyone knows?