Ok i dont have a evo but i thought i'd ask cause there a quite a few 35r'd evo's. anyways when i try to run more then 22psi on my manual bost controoler i get a fluttering sound from my turbo and i can see my boost gauge going back and forth pretty fast like 2-3psi difference the more boost i give the worse it gets.... I was wondering if you guys run a lot of boost on the mbc without problems... I heard a electric boost controoler would help a lot. any ideas to what is going on

 

are you saying you can't boost above 22psi? What kind of wastegate are you running? What kind of BOV? I would check those first. sounds like something is not holding boost.

 

mine was doing the same thing, i just tightend the adjustable screw for my bov, not sure if yours is adjustable but worth a try

 

could be wastegate flutter, could be your BOV....

Are you running a Tial 44mil?

could just be surging too....

 

Its because you have a 1.8t

 

1.8T's nevAr loOse yo.

Check your bov.

 

i have a HKS SSqv the screw is all the way loose... hmmmm i think i tried tighting it before but had no luck.. Im running a 38mm wastegate with a 1 bar spring... I think im going to try a EBD and maybe change my BOV to a tial 50mm

 

Don't touch the screw on the back of the SSQV. Leave it all the way out. Pull all the lines off the wastegate and do a run. Don't over boost though. If you still have the problem then its a wastegate issue.

Also, are you sure you have a 1 bar spring? Have you comfirmed it?

 

sound like a wastegate problem, not a boost controller issue

 

well below 20psi its rock solid, I pulled the wastegate line before and it went to 40psi and i thought i blew the motor lol... Man it got to 40+ psi fast.... Yes i ran the wastegate line to the intake mani and it help 14-15psi steady

 

It sounds like you have a MBC problem if you could get over 30psi w/o issues and w/o the lines hooked up.

 

yeah im going to try a EBC and hopefully it will hold steady boost.. Well thanks for the help guys

 

You most likely have a serious boost leak. A MBC will work just fine.

 

i have zero leaks, all my IC hose's are T-bolt clampped

 

Sounds like compressor surge. Most 35R's will surge on a 2.0L engine, surge even worse on smaller engines.

Generally the surge will get worse the higher you turn the boost. If the sound is mostly once the turbo gets to full boost....does it go away after engine rpm climbs a bit? If so..definatly comp surge and pretty much nothing is going to fix it (adjusting bov, wg, mbc).

only way to fix comp surge on spoolup is to make the engine bigger or make the turbo spool slower, or run less boost.