Thread: Blitz blow off valve = compressor surge?

i have the same problem and i fixed it today, u need a very strong vacume soruce, and lossen the adjustment screw,

How long is your intercooler piping? If the piping is too long on the cold side it will always give you a little surge with a t25. I had to loosen my greddy type-s bov almost all the way to completely eliminate surge. Your probably going to need a different bov.

It's basically regular length for a front mount.

I have the same problem on my stock gtir...When I boost under 5 psi it surges..anything over that and it opens just fine. Boost gauge is reading 15-16psi vaccum. Im running an HKS super bov. Can't figure mine out either. Think it will stop doing it when i I install a bigger turbo?

Mine doesn't surge quite that bad but it's set up basically just like yours but my bov is next to the battery

u can tie all 4 throttle vacuum nipples together and use that as a vac source with your bov, it'll help with the surge. but surge with less than 5psi is so minimal, my bov doesn't open up unless im boosting closer to 7-8psi.

i use the stock vacuum line for a sheepdog prof recirc'd bov which doesn't open up till 7-8psi, i've had it this way for nearly 2.5yrs daily driven i don't have any issues.

it's really more of a flutter than a full blown surging of the compressor. It still opens, just delayed.

You can't really "check for surge" under no load conditions, as these conditions are basically non-existent while driving.
If it surges with you driving around, it could be the following:
-The BOV is too tight
-The signal is not strong enough for the BOV
-The turbo is mismatched to the engine
-You're driving in the surge zone, change your driving habits