How can you tell if your BOV/Bypass is too small. I have a bypass routed in to the intake. This is from my old ProCharger P600B kit. I'm now running a Novi 2000 set at "about" 15-18 lbs of boost. Head unit has a 2.75" pulley. Have'nt taken it past 4500 rpm's due to lean condition. Anyway, what symtoms will I notice if the bypass is'nt flowing enough CFMs? Bucking when letting off WOT? Thanks for any sugestions.
Bypass valve too small?
- Thread starter ROADWARRIORSVT
- Start date
There really aren't any symptoms that I know of but it does cause a lot of stress on the impellar and seals by not having a big enough bypass. That's the cause of my Vortech seals going out, my bypass wasn't big enough for the PSI I was running.
Thanks Booya. Anyone else?
When you bring it up to a high rpm under boost and let off the gas, does the car surge or buck?
Are you using one of the little black bosch bypass valves?
I would upgrade if you are, those things are only rated to around 8-9 psi.
Are you using one of the little black bosch bypass valves?
I would upgrade if you are, those things are only rated to around 8-9 psi.
Have'nt gotten into full boost yet due to running lean. I'm just concerned that the bypass for my small ProCharger is'nt gonna cut it for the Novi running 15+ lbs. boost.
SVTHorsnake
Banned
I picked up a TurboXS off NASIOC for about $130 shipped with 200 miles on it... it was for a WRX but I just take off the adaptor and clamp the pipe down and I'm off... it's loud but good up to around 30-40lbs from what I hear... you could always go that route just to be safe.
Will check into that. Thanks.
its not really a matter of being too small....
the issue with a low quality BOV is a matter of it bleeding off extra boost pressure.
i.e. the "flapper valve" that comes with procharger kits.
the issue with a low quality BOV is a matter of it bleeding off extra boost pressure.
i.e. the "flapper valve" that comes with procharger kits.
SVTHorsnake
Banned
and a better quality BOV such as a TurboXS will more than cater to that problem...:beer:
SVTHorsnake
Banned
http://forums.nasioc.com/forums/showthread.php?threadid=511618
not a TurboXS but still good quality...:shrug:
not a TurboXS but still good quality...:shrug:
are you saying that your bypass valve blows off to outside air-like turbo systems do? do you have a blow through style mass air meter?
bryan
Mine? I have a blow thru type Pro-M Univer, vented back into the intake. I'm thinking when I up the boost, I better upgrade bypass valves.
as far as turbo systems go... some vent to the atmosphere, and some vent to the intake tube after the mass air meter... it depends on where the mass-air meter is located.
a turbo and a centrifugal supercharger setup is identical on the intake side..
as far as cars with mass air meters go, you must have the BOV before the mass air meter if you want it to vent to the atmosphere, and still maintain driveability. that way, it is venting air that hasnt even reached the mass air meter yet. that is called a "blow-thru mass air setup" because the mass air meter is on the pressurized side of the supercharger/turbo.
a pull-thru setup is when the mass air meter is on the intake side of the supercharger/turbo... therefore, all the air in the tubing is metered, and the engine expects to recieve it. It calibrates the air/fuel ratio accordingly. During shifts, and part throttle operation when the BOV is open, it is venting metered air... so it must be vented back into the system.
If you vent a BOV to the atmosphere in a pull-thru system, your car will run extremely rich during part-throttle acceleration, and between shifts. itll also idle real funky... (no, it does not sound like lopey cams...:bored: )
youll foul your plugs... we tried it in my buddies WRX. sucks.
options:
1. Get a procharger... it comes with a blow-thru setup.
2. Plum a blow-thru setup.. its real easy.. youll need a retune though.
3. Just recirulate the BOV... its not the end of the world.
:beer:
Homer
:thumbsup:
SVTHorsnake
Banned
yeah, I vent to the atmosphere... it runs rich between shifts but it makes for a cool flame:thumbsup:
I was worried about doing it at first. But then I noticed anybody with an aftermarket BOV on a WRX is having to bypass the return and haven't had a problem... mine hasn't given me any issues as of yet...:shrug:
this is exactly what i was getting at. i just wanted to get all the facts before assuming too much ya know. and if my memory serves me wrx's are turbocharged...right. which is why they can blow off to outside air because the air thats being blown off isnt metered yet by the mass air. also dont get the blow off valve and the waste gate confused hehe. dude you need to re-route that air back into the intake-but thats just my opinion. to each his own:-D
later,
bryan
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