SD might be the next thing I do...just need the 4bar and tune right?

 

Yessir!

 

But the OZ comes with one from factory, is the aftermarket really that much better?

 

I agree on that. You will definitely feel the difference when you are cornering!

oh and I ordered the omni-power 4 bar MAP sensor too! can't wait!

 

Okay, I got one for you guys. About a week ago I've lost boost pressure.

It started with randomly briefly stuttering during cruise. Then one day under light throttle I heard my exhaust note change and lost boost. Basically drives like it's NA now. If I wasn’t SD I'd suspect it to drive like crap.

So got home popped the hood, I don't see any pipes disconnected, since my exhaust note changed I thought it was my waste gate and changed my forge to a stock 8 one. That didn't help it.

Thought okay it has to be the Synapse bov changed that to stock. No change.

I'm pulling a strong 19-20 vac at idle but it takes about 75% throttle to just get 2 or 3 psi.

I don't hear any turbo whine, no smoke, vac is fine, thoughts?

 

Check the wastegate arm see if its tight. If its too loose it will do that.

 

Second the wga. But also check your downpipe. Mine actually came loose once causing similar issues. It was a gradual change in the exhuast note and boost pressures. I could not tell until I got under the car and could physically see the gap.

 

Almost sound exactly like what my buddy delt with on his STI last year...Exhast note subbenly changed and lost almost all boost...turned out is was the little internal flapper on his internal wastegate...It had broke off...So it was wide open, dumping all possible boost right out, except when he was like in 3rd gear and stopmed on it, then it would get maybe 2 to 4 psi for just a few seconds....No idea how it broke off, but it did...If all else fails, you might have to pull it apart to check...Just an idea

 

couldnt he just unhook the wastgate and move the flapper to see if its still there should make a noise when it shuts

 

I suppose it could be possible to break a wastegate flapper if the tension was too low. I imagine that a loose arm could "flap in the wind" with sufficient exhaust pressure and the repeated banging against the housing would eventually fatigue the metal to the breaking point.

 

I would think that would also cause I nice rattle sound by that area if you rev it up and let the rpms drop. That's the sound mine made when I didn't have the preload correct.

 

funny you mention that cause im actually dealing with that now...how exactly do you set the preload? (btw if anyone has an extra wastegate that isnt rusted on the locking nut lmk)

 

Mine happened because I pulled the cold side off and left the hotside on the car ( I REALLY did not want to deal with all the lines and the rad at the time)so When I put it back on I did not clock the turbo correctly.

To fix Mine I had to pull the whole thing off and re clock the turbo correctly. For you if you haven't messed with something that changed the clock of the turbo then you should be able to just pull your wga off and adjust it down slightly. After you bolt the wga back up to the engine you should have to slightly pull on the arm in order to reach the wastegate flapper. If you can just slide it on and off then its too loose.

 

oh ok...ill have to try it this weekend

 

You shouldn't even have to do that.. the wastegate arm is a spring with a tension screw which is the arm attached to it. Just pop off the c clip with a screw driver, pull the arm off the acuator, and start turning the arm in the clockwise direction like you would tighten a bolt. The arm should be something around a 1/8" or so below the closed position of the actuator for preload but you can go further if you like to add more preload. Once you get it about 1/8" down just use some arm strength and pull the arm up so you can slip the rod into it.

It takes quite a bit of force to move the arm by hand but its not impossible. Since your springs are only the 5-11psi range it will be doable without tools. Something like a 28psi spring would take a lot more effort and probably a pair of vice grips to make it happen.