Compressor Surge w/ Blitz DD Bov

[jdm_s14_zenki]

EDIT: PROBLEM SOLVED!!!
If anyone has a similar problem with your blitz bov or you get alot of chatter (compressor surge) or your bov is leaking vacuum or boost, this is what you do to get rid of the chatter(if its because of your bov not functioning properly) and to make it bullet proof against boost and vacuum leaks:

Heres my story:
Ok, so I bought this bov 2 days ago from some guy that had it on his WRX. Looks very clean, so i bought it. When i first installed it, i noticed that the adjustment screw was all the way loose. So i left it alone then drove around. I get major compressor surge. Cant even hear the bov at all at any rpm. all i hear is fluttering, SO i tightened the spring, and of course the same thing! then i backed off the spring a few turns. same thing. Im just curious to see if anyone had this problem with this bov. Its not leaking boost or vacuum at all!! so thats not the problem, and yes its correctly hooked up.

Heres the solutions/maintenance:

If you loosened the adjustment screw all the way and you still chatter that means either your piston is stuck closed, or your spring tension is too tight. In my case, the spring tension was too tight

If you piston is stuck simply take the bov apart from the top (4 allen bolts) and slowly and carefully open it up. the spring might pop out at you like it did me :[
Next just take everything thats inside the bov (piston, spring, inner wall of the bov, ect,) and clean it with some carb cleaner or something. Make sure that the piston is nice and smooth and it smoothly plunges inside the bov with no resistance. if needed, take some fine grit sand paper and sand the inside defects until the piston moves freely. do not screw with the rubber part of the piston.
Next you will need some kind of lubricant. I used air compressor oil cus thats all i had laying around. oil up the piston and the inner cylinder of the bov.

Next, you will need some gasket sealer. I prefer the high temp, oil resistant (black stuff in a black tube from autozone) gasket sealer. anywhere where theres a paper gasket, or metal to metal parts that you have taken apart (top cap of bov, between bov and flange, ect.) apply a neat and thin layer to it. if the layer is too thick, when you tighten the bolts down, the gunk will squeeze into the cylinder/piston area, hindering the free movement of the piston.

Put everything back together. Apply the gasket sealer or teflon tape if you have any to any screws that go into the bov. for instance, the adjustment screw needs to be sealed off good or else you might leak boost/vacuum. Also, do the same with the vacuum hose fitting that goes into the bov. both blitz bovs i had leaked vacuum from there. Check for cracks in that fitting area as well. mine was over torqued and it cracked so i had to use gasket sealer to seal it up temporarily. then use jb weld if you dont plan on messing with that fitting ever again.

All this work will pay off. There is NOWHERE for the BOV to leak as long as you use the gasket sealer in the right places!

To reduce spring tension, simply cut the spring shorter. I cut about a 1/4 of the total length of the spring. i had the standard 18psi spring. Dont cut the spring too much or you will be adding a crap load of washers under the spring to make up for the loss in tension.

After this is all done, you need to tune your BOV. Heres how to do it.

Replace the adjustment screw back into the top of the bov. when you tighten down that screw, you will notice tension all of a sudden. thats when the adjustment screw starts tightening the spring. at that point, turn the screw about 1/2 - 1 turn, then use the lock nut to hold it in place.

Try driving around and see how you like it. The chatter should be gone at this setting no matter what rpm or vacuum/boost level you are at. If you like it, leave it. If the car starts bucking, you are loosing boost, or vacuum, thats because the spring is opening under vacuum. Its too loose, so start tightening that screw aanother 1-2 turns, then try again. repeat these steps till you get it dialed in.

I have mine adjusted to where if i let off the throttle in very low rpm (the point between vacuum and boost on your boost guage) there will be a little tiny bit of chatter. but you can barely hear it. at about 1-3 psi boost, you should not hear the chatter at all and only hear your bov woooshing. especially at high boost, you should only hear the bov. no chatter.

This stuff worked for me. It will work for you, dont waste your money buying another bov. Just fix it and dont worry about it for a longg time!


So ya, its 1am right now and i gotta work at 8 am, im really tired so if i miss-spelled anything or i dont make sense, just let me know and i'll fix it. Hope this helps you guys out, cus ive been dealing with this damn problem for over a year now and i FINALLY FIXED IT!