fastcarfreak

So, after about a year of not knowing why my boost is fluctuating like mad, and why my power feels like its not all there, I think i finally solved my problem. My father and I finally got around to rigging up something that would allow us to pressurize the system. He got some pvc pipe end piece and connected an air stem to it, and then connected it to the piping's end with a coupler and clamps. Worked like a charm because i finally found what i hope is the culprit. The welds on my blow off valve flange have failed, but its not visable to the eye. when we applyed compressor to the stem it immediately caused a very loud hissing. When you put your hand near the blow off valves welds, you could feel a rediculous amount of air just gushing out. And this was at just over .5 bar of pressure. Can you imagine how much air would come gushing out at the nearly 2 bar of boost that i have run the car at. The turbo had to have been blowing well out of its efficiency range to compensate for the loss of air.

I wonder how much power i have been missing out on for the last year or so. Unfortunately im gonna have to retune the car, because im pretty sure it was tuned with the boost leak.

Anybody ever have a similar problem as to mine? Can you tell me if you noticed any amount of difference after the problem was fixed....

Am I wrong to think that this boost leak could potentially cause a boost fluctuation problem?

Adam

black beauty

i know exactly what you mean. But not with my fd though, it was with my dsm...boost leaks are the devil...

GoodfellaFD3S

iTrader: (213)

Wow Adam, I can't believe you had that problem for that long! Kudos to your dad for helping you rig up that pressure setup. Btw, when and why were you running 29 psi of boost?

fastcarfreak

I guess the reason i had a problem for that long is because i was just hoping it wasnt there at all, lol. Maybe a little bit of denial. Plus i never really knew how to find the leak. Got it all welded up today and am waiting for all this rain to clear so i can hook the wideband up and go out retuning if it needs it.

Oh, about the really high boost (actually fluctuated between 24 and 29, but mostly stayed around 25-26) I was getting a lot of crap from some guy who runs 11.40s with his late 80s transam with his spray, so i decided to go out for a little tuning session and just kept upping the boost on c16 untill i felt i wasn't getting much more benifit Then i used my dual stage water injection for that added protection. Needless to say, the look on his face after the race when he seen me walk by him at about the 1/8 mile was just priceless (he has slicks, i have drag radials, so he was able to gain a couple car lengths at the beginning). He wouldnt even shake my hand after the race, and we are somewhat boys. I guess a 30 something year old driving his american muscle car with a ton of years of drag racing experience, didnt like getting beat by a 21 year old import driver with only a few years of racing experience. lol. This was done on the street by the way, because i dont race at the track.

He spent the winter turning his 11.40 car into a 10 second car with hopes to come back and get his revenge. He put a big cam, a cage and upped his nitrous shot

I just hope that with my newly fixed problem he has another thing coming

fastcarfreak

oh and the guy who did the welding said that he could almost guarente that the weld was bad right from the beginning and that i probably had this problem all the way back when i first had it done by the place i had it done. which is like 2 and some change years.... heat and boost probably just made it worse as time went on..

Adam

fastcarfreak

IM HEALED!!!!!!!! I took the car out for its test drive and my boost fluctuation is gone, gone, gone!!!!!!! I can not be happier right now. I cant really tell the difference in power off the wastegate spring (10 psi) but there definately is a difference at 15 psi. It holds boost nice and solid so im sure im actually getting full power potential at 15 psi. I just hope the boost holds solid at 25 psi where i would like to set my high boost back to. (fingers are crossed)

Anyone feeling like there car is running a little sluggish, or not able to keep solid boost, i definately recommend pressure testing your system.

Now if i can get my car to a damn dyno

Adam