Greddy Type S bov problem.. :(

[Zach_SR20]

so, my greddy bov came in the mail today (thankfully), and i dont know too much about blow off valves BUT i do know how to hook this one up. took my hotpipe to a local welder and had him weld the flange to it. after installing the bov and really mashin on the gas to test it out i noticed the car would almost die out. i found out after lookin online for a bit i foudn out the bov spring didnt have enough tension, and when it would "blow off" the spring wouldnt close the atmosphere-hotpipe gap soon enough, so it would almost stall itself. now i tightend the bov screw on top to where it wouldnt nearly cut off, buuut i noticed something different now. firstly, when moving the throttlebody with my left hand, and holding my left hand next to where the air releases, i cant feel ANY air come out. i dont hear it release, or anything. the type s is supposed to have a screechy sound when it releases pressure correct? well i've only heard that once, and just barely (before i adjusted the screw). i want it to blow off when it should, and make some sort of a noise so i know it is blowing off. what could be the problem??

[jspaeth]

so, my greddy bov came in the mail today (thankfully), and i dont know too much about blow off valves BUT i do know how to hook this one up. took my hotpipe to a local welder and had him weld the flange to it. after installing the bov and really mashin on the gas to test it out i noticed the car would almost die out. i found out after lookin online for a bit i foudn out the bov spring didnt have enough tension, and when it would "blow off" the spring wouldnt close the atmosphere-hotpipe gap soon enough, so it would almost stall itself. now i tightend the bov screw on top to where it wouldnt nearly cut off, buuut i noticed something different now. firstly, when moving the throttlebody with my left hand, and holding my left hand next to where the air releases, i cant feel ANY air come out. i dont hear it release, or anything. the type s is supposed to have a screechy sound when it releases pressure correct? well i've only heard that once, and just barely (before i adjusted the screw). i want it to blow off when it should, and make some sort of a noise so i know it is blowing off. what could be the problem??

You don't really build any boost at all when the car is in neutral or not in gear.

That is why it isn't blowing off when you are under the hood using your finger on the throttle.


If it is hooked up right, it should blow off when you build up a few psi of boost and then lay off the throttle quickly.

If it's chattering, it's too tight. If it doesn't close all the way and makes you bog, then it's too loose.

The latter is something that you have to deal with if you are running MAFS (instead of MAPS) and you want it to blow off to the atmospere.

[Zach_SR20]

thanks bro!! i guess i just gotta find that sweet spot on the bov adjustment. i'll mess with it tomorrow some more. i was on my way to school tonight after i thought i had it set right, whenever i hear this real loud POP!! and then my car cut off. thought i blew my turbo, but my hotpipe just blew off of the intercooler piping. scary shit eh?

anyways, thanks again for the advice!!

[jspaeth]

thanks bro!! i guess i just gotta find that sweet spot on the bov adjustment. i'll mess with it tomorrow some more. i was on my way to school tonight after i thought i had it set right, whenever i hear this real loud POP!! and then my car cut off. thought i blew my turbo, but my hotpipe just blew off of the intercooler piping. scary shit eh?

anyways, thanks again for the advice!!


Ummm sounds like you had it WAYYYYYYYYYYYYY to tight. It didn't blow off at all and blew off your hot pipe.

First of all, you are lucky that the hot pipe blew off, because if the BOV doesn;t blow off, that pressure wave can either A) Break your throttle plate and send the screws into your engine, ruining it or B) wreck havoc on your compressor wheel (surge).

Once you have the BOV working correctly, go back and recheck all of your silicone couplers. They should not EVER come off.....people push enough air through these things to make 600+ hp and theres don't come off.

If they are on properly, the metal on the clamps should be so tight that there should be no way for it to slide over the bead (you should have beaded ends on your piping)

[Zach_SR20]

well, i dont think i rly tightend the one that blew off down very good when i put the hotpipe back on. its a serious bitch to get to. i have to use a wrench on the small nut that tightens down on it, not a screwdriver unfortunately :-/