swinke

Wouldnt there be an advantage in having a BOV between the IC and the TB on the Procharger HO setup? Besides the cool noise it makes.

jesseenglish

Other than to replace the flimsy bypass valve that comes with it and the cool sound it makes, not really IMO.

12SecZ

hehe... Snow then desert for 2 seasons and our cheap valve is toast.

The hehe part is I am not in a desert where it snows hehe so Jesse will be the first to let us know. I want to replace my current valve with a $300.00 valve but man, I just don't make enough money.

swinke

Our K-Mart surge valve is operated by manifold pressure. It was my understanding that a true BOV is put in place to reduce compressor surge. How will that work if the throttle slams closed at high boost and the manifold pressure instantly drop but the pressure on the compressor side of the TB butterfly doesnt? You still get surge to the compressor, right? The valve would never open? How could it. It wont see the surge.

jesseenglish

Our bypass valve is in a normally closed position. It opens with vacuum. If the TB closed the manifold goes into a vacuum and opens up the bypass valve.

You don't get compressor surge in a supercharger application because there's no wastegate to get stuck closed.

swinke

WOW, thats funny. It never occured to me that it was vacuum operated. I always thought that BOV's were pressure operated to keep a certain pressure limit from being exceded on the compressor side and the waste gate on a turbo handled the manifold side pressure limit issues. So......can I vent it to open air just for the cool noise? Or is this a bad idea?

jesseenglish

The way our system is designed it's a bad idea because the valve is used to make air flow easier into the intake when you're not on boost. Without it all of your intake air would have to be sucked through the SC head, through the intercooler and finally into the intake. The bypas valve shortens that trip to improve performance.

If you opened it to open air you'd be sucking unfiltered air into your intake.

Z1 Performance

iTrader: (564)

not with the stock MAF you cannot vent to air...must reroute it.

What BOV's are $300? they are typically under $200, and some under $100. Unless yours leaks boost, I would not bother replacing it

swinke

Hadnt thought of that....so how bout a medium sized (3 or 4") K&N attached to the tube? Cool noise, clean air, 'sall good?

jesseenglish

They do leak a little bit of boost because the valve flap isn't very tight fitting, but not really enough to be concerned about IMO. It really is a POS valve.

swinke

Air comes in filter (past BOV port), threw compressor (past other end of BOV port), threw IC'r, then into MAF. How would the MAF see the missing air?

jesseenglish

Well most of the BOV's that I've seen have a very small pipe diameter to make that cool sound. So, you're going to lose a lot of performance when you're not on boost because of the difficulties of sucking air through the intake.

swinke

If the MAF was on the suction side of the compressor it would see the air come in and read it but then the air wouold be released before the manifold and would cause a mireading. The procharger setup leaves the MAF on the pressure side. I dont understand how the MAF would misread the air?

jesseenglish

You could probably actually gain performance when not on boost if you put a larger diameter bypass valve to replace the one we have. Not gonna get the psshht sound though.

jesseenglish

It should be fine from a MAF standpoint AFAIK.

swinke

HEY! I got it! Put a Co2 tank in the spare tire compartment with a line running to a solenoid under the hood. Hook a momentary switch to a timed on pulse relay with about 1/2 sec window. Everytime I let off the thottle I get a 1/2 sec of SHTTHAHH. Whatayathink? Could sell it maybe? ROTFLMAO!

Z1 Performance

iTrader: (564)

is ther a pic of where this valve is mounted?

swinke

Ya know! I think I could market this with the fake intercooler for the front grill to those guys that buy the MAG WHEEL plastic hub caps! You know they got fake spinners for the fake mags now? Have you seen that crap?

Make a fortune! Looks FAST! Sounds FAST! Aint FAST.....those guys. You've seen em'.

jesseenglish

I knew this diagram would come in handy again. The MAF is right before the Throttle body.

elektrik_juggernaut

i'm replacing my surge valve with a BOV.......hopefully before next winter.......the surge valve's rubber diaphragm will wear out cause its exposed to air......i will feel much better when my engines head gasket is in the hands of a brass valve, instead of a rubber diaphragm........if the valve was a normally-open type, i wouldn't sweat it.........broken valve in the normally open position doesn't scare me.......broken valve in the normally-closed position does