Talon_66

iTrader: (6)

under partial throttle my Forge BOV flutters, ever since I installed my new Exhaust.
Also when I let off to shift it has one big burst followed by another small flutter.

Help?

Maybe I will switch back to my OEM BOV

no0odlez623

isent that sopposed to happen? i think it sounds cool... if its good or not for your car idk... but my stock bov flutters a little every now and then

STi2EvoX

The only DVs or BVs I will even consider using are the oem or the works modified oem. Aftermarket BOVs cause nothing but problems.

EvolutionIX_MR

My BOV flutters A LOT at partial throttle to...I never really worried about it to much, but I hear its compressor surge...

STi2EvoX

^ It is compressor surge, but if it's mild then it really isn't going to hurt anything. If it's bad then you are going to wear the turbo out prematurely so I would definitely keep an eye on it. It will, however, cause the turbo to loose it's spool between shifts and cause the motor to feel boggy, especially when combined with the fact that if it's a vent ot atmosphere type valve you will become overly rich when the throttle plate closes as well. This will further cause the motor to bog down between shifts. Just a thought... but go back to the oem valve or if higher boost pressure holding is needed, go with a works "re-worked" oem DV.

Mike@Forge

iTrader: (23)

A fluttering valve is NOT an indication of compressor surging nor is a functional problem in any other way.

It's a normal effect caused by the valve responding to changes in pressure and vacuum between the charge piping and the intake manifold like it's supposed to do.

Please read the threads linked to below for a better understanding of what is and isn't surging and some more in depth valve mechanics.

Compressor surging:
https://www.evolutionm.net/forums/sh...d.php?t=285733

Valves:
https://www.evolutionm.net/forums/sh...d.php?t=209640