Not sure if this is similar to the Q or the Alpha Q but I am getting a good amount of mid throttle flutter. Low throttle or full, no issue at all. Trying to pass someone or speed up a bit, it flutters and bucks like crazy.

I was shipped the BOV with the 8 PSI spring, I idle at around 450 mmHg (17.5inHg). This is higher than the 9 PSI spring, should I opt for the 11 PSI or just stick to the 9? Problem is I dont want to try a bunch of springs at $30+ each spring. Good BOV since WOT at 6th gear goes passed 28 PSI on my gauge by a lot, guess the stock one wasn't doin it's job. Maybe TiAL Sport can chime in.

 

just email/call tial and send your spring out and they will send you another... just pay shipping iirc

 

Edit:

mid throttle flutter isn't the BOV, it's the turbo going into surge

you are feeding more air to the engine, rather than the stocker leaking and recirculating some of it in charge pipes.

 

I just don't understand how I can be feeding more air to the engine at 10-12 psi now rather than before. What do you suggest I try doing? I can't justify a turbo upgrade right now.

 

you're feeding ALL the air now not just 80-90% like you were with the leaking bov.

best thing to do is down shift a gear or two

 

I read around and noticed some people are running the vacuum line directly to the intake manifold, not sure if that would help, but I am goin to try it. Would the internal spring make that much of a difference if my idle is at -17.5 inHg, slightly higher than the 8 PSI spring given to me?

As for downshifting, I was in second gear tryin to get out of a lane... Didnt wanna go WOT and be that guy in traffic. What if I am racing and giving partial throttle through the turn, seems like it would flutter and cause me to let off the gas in the turn. Would hate to get rid of this BOV if I can't use it with a stock turbo.

Update: Happens in ALL gears. It's kind of like a flutter, then it will blow off. I can work around it by letting out the gas when it happens, but I can't drive like this. Hope someone else with a TiAL BOV chimes in.

 

I used to have this problem all the time. Only with VTA blow-off valves though. I guarantee if you find yourself a nice re-circulated blow-off valve, you will avoid the problem. Even simply switching back to your stock blow-off valve will eliminate the problem.

 

you're describing two completely different types of surge.
for starters, you need to be running a 1/4" ID reinforced line directly to the manifold (cheap at autozone)

after that has been completed you need to see how it acts.

surge that happens when you are on the gas (mid throttle as you put it) has 0, zip, nada to do with the bov, you are riding the left side of the compressor map and it's the turbo surging - it would happen if you had no bov at all too

you say it does this noise then blows off? only thing that would cause this is a leak in the line - a gash, tear or hole.

 

The QR is TiAL's new recirculating BOV.

 

OK. I wasn't too sure if that was true about the vacuum line. I will give that a shot and I will replace my recirculating hose.

Thanks for the info.

 

I am also running the TiAL QR on a stock evo 8 turbo and it works fine. It can be a bit noisy over the stock bov.

 

Well I replaced the vacuum line with 1/4" directly to the intake manifold. I even got the high pressure stuff just in case that was the problem.

Replaced recirculation pipe with another radiator hose, made sure all pipes are tightened... Still same problem. Thought I would replace the radiator hose with the ETS hard pipe that I had... same thing.

Only thing left to try is a new spring, then who knows from there. Spac3clown, what PSI spring are you running?

 

i think you need a 10 psi spring.

 

Is it happening in every gear or just the higher ones?

 

What rpm's is it happening at?