Well I hooked up the leak tester to the turbo again. This time I used the new fitting so I was able to hold 15 psi steady while I sprayed soapy water EVERYWHERE lol. Only found one very very small leak on one of the IC couplers. Couple of twists with the ratchet fixed that. Sprayed every coupler, every injector, IM gasket, TB gasket every single vacuum hose and nothing bubbled so thats good I guess?? Did blow my dipstick out a couple times until I put a bungee cord on it lol. Pulled my Forge wga off and put on the stock one only to find it has a much smaller diameter fitting for the boost source. Didnt have the time or patience to go down and get a connector so I just slapped the forge back on after adjusting it all the way down (only one full turn more than before).

Took it for a drive and now I am hitting about 12 but once again turning up the MBC is not doing anything for the boost. bypassing the mbc all together I get the same result about 12 psi, however this is the 14-20# blue spring that is in there now so what gives? May just have to get that adapter and try stock wga. My mbc j pipe, and forge wga all take 1/4" line while the stock wga I have takes a 1/8" dunno whats up with that. Maybe I dont quite understand how the WGA works.

 

I'm curious, what kind of boost gauge you using. I only ask cause mine ending up weirding out on me after a few weeks and actually shows its boosting at 14psi when compared to what ER shows at 11psi on the dyno. Basically, the mechanical part inside my gauge is a little faulty at boost, yet show true in vacuum. Do you feel an absolute difference in the way the car drives? Are you seeing anything obvious in your map/tune when plugged in?

 

Oh yeah its different I know my car very well inside and out just ask RyanCB lmao. I run just a glowshift boost gauge and it is off by 1-1.5 psi lower than actual per ER's readings as well. This rise to 12 psi has given a little more life back into it but still not where I should be, it drives just fine pulls good just not reaching full boost so WOT doesn't pull like it should and damnit I put alot of work into getting it to do just that .

Can anyone confirm my method of understand how the wga works? If the gasket ruptured this would result in higher boost not lower boost correct? Regardless I know its not leaking since I sprayed it with soap too while checking for leaks. Am I correct in thinking a weak spring is the ONLY way that the wga could cause a lower boost?

 

It was worth a shot to ask....lol. I figured the worst that could happen is...Throw enough oddball questions at ya, maybe it flip a switch and a lightbulb would pop on and you would be like....HOLY S#@T I think I just might of solved the issue. lol. Maybe someone will jump in at some point soon and really have the fix needed

 

Found another thread with a dude who had the EXACT same issue right down to the fact that the boost dropped on the same run like mine did. Most people on there said Wastegate was the issue. Unfortunately for me That guy already had a new turbo setup on the way so his issue was fixed when he switched everything out.

 

I cant tell if you are being goofy, or what. A WGA works by having a spring inside, and a boost source connected to the top. As pressure increases in the intake, it fights the spring, and eventually wins, which causes the arm to stretch out.

When the WGA arm stretches out, it pushes the flapper open, releases some pressure, and prevents the car from continuing past the safe boost.

If the WGA spring were weak, you would boost less and it would open sooner.

If the WGA spring were strong or stuck, you would over boost.

If the MBC is between the WGA and the boost source, all it is doing is keeping pressure from reaching the WGA and thus preventing it from opening to bleed off pressure. That is why an MBC can't lower boost, only raise it about WGA setting.

If you are boosting the same with and without a MBC, then that's the problem (the mbc is not working). You can confirm that by just hooking up your air compressor to the inlet side of the MBC usign a pice of vacuum hose, and slowly increasing pressure. at 15psi, it should crack open and start loosing pressure (or whatever it's set at).

 

Maybe you should add more preload to the WGA? It sounds like your spool got better but maybe it needs just a bit more preload to get it back to where it use to be?

 

I would concur with hornstars diagnosis though for a test I'd just slap the hoses together and bypass the mbc for a test.

Sounds like the mbc isn't bleeding off wga pressure to up the boost.

 

Ok so my understanding of how all this works is correct. Now here is the thing. bypassing the mbc by just hooking the WGA up to the boost source should bring me to the minimum boost of the spring correct? Well I have the blue spring in there now which is 14-20 psi spring yet I bypassed the mbc after install to find out if in fact the mbc was bad. I assumed I would see around 13 psi but yet I still only hit 9psi what would explain that?


This most recent attempt to fix this I did add more preload. The max infact I bottomed out the rod, this brought me up to about 12psi so not sure what exactly that tells me.

The little hole in the back of my mbc was blowing out air steady while I was doing the boost leak test dunno if that helps or not. I bypassed it halfway through the test for one less leak to listen for.

Also anyone notice there egr solenoid leaking when doing a leak test? I usually pull that big vacuum hose off on top of the IM and plug it. That has always been there though so cant be my issue now.

 

Maybe the flapper is gone?

 

My spool would be wayyyyyyyy down if the flapper was straight up gone. My spool is actually much better now that I reclocked the turbo and the wga is able to hold the door closed. Thinking about clocking the turbo even more so I can put more of a preload on the wga which I think should give me higher boost but I kinda think thats a bandaid approach instead of figuring out the actual issue.

 

Ok I put the stock wga on (first time I have ever ran with it). 12psi with mbc connected and all the way down which suggests that the wga is working properly. 10 clicks up with mbc still 12psi. Looks like next thing to try is getting ahold of another mbc and seeing what that does. Still doesnt explain why I only seen 9 psi with the 14# spring in the forge though :-/

 

You can test the WGA with attaching your air compressor to it. I put a vacuum hose on the tool that fills up inner tubes and stuff, and then connect it to the WGA nipple. You can adjust the pressure up on the air compressor, and watch the arm on the WGA. It will start to open at like 5 psi and fully open at 10 if you have the smallest forge spring.

Test it with your blue one, and see how it reacts. I bet if it's a 10-15 psi spring it will start opening at like 10 and then fully by 15. The stock evo spring is fully open at 12psi in my experience. If your blue spring forge opens easy, like you can just yank the arm or something and have it open right up, then it's messed up. If it doesn't, you probably didn't have preload set right.

Preload is just supposed to keep it from opening with lightpressure and the exhaust pressure pushing against the door. I've found that basically setting the eyelet to the point where it can just slip on and off, then giving it about 3 full turns does the trick. Too little preload, and boost is slow to build, too much and the arm can't fully extend and you run the risk of overboosting since it limits the flapper door travel. Better to get the WGA nicely set so it holds but not any stiffer, and then use MBC or electronic boost control to up it from there.

 

If its blowing constantly no matter what the pressure is sounds like the MBC is stuck wide open. Try blowing in it with your mouth see if its too easy to move the ball and spring. Your mouth can only produce about 2psi unless you do special risky moves to increase the pressure.

The WG spring pretty much confirms that the MBC isn't working if it just hits 9psi. Just because you have a bigger spring in there doesn't mean your going to hit that level of boost unless there was a pretty serious leak, the turbo is big to be overrun by any small leak. A really common one is the EGR lines blow off on the evo dont know if you have that issue.

 

I still dont know how you clocked the turbo differently when there is a pin guide between the hotside and center cartridge .