blow off valve

[revharde30]

can u put one on a super charger

[gotKRAUT]

centrifugal superchargers usually run a recirculation valve...or even the blow off valve...blow off valves don't function as well as recircs on turbo/centrifugal superchargers but they "sound cool"

but as far as screw type superchargers you dont need one...the second you let off the throttle the supercharger slows down...no issues of back spooling the supercharger...

[revharde30]

i got a g60 and im putting a motor in it and i want the cool sound

[DIRTE30]

Originally Posted by revharde30

i got a g60 and im putting a motor in it and i want the cool sound

RICE ALERT!!!!!!!!!

[AlpineSixAndSeven]

^lol yeah..... there for turbos if you want that sound turbo the thing....

[saltshaker185]

your best bet with the supercharger is a bypass valve instead... technically you could run an atmospheric blow off valve but im pretty sure you will lose power as a result...

[gotKRAUT]

Originally Posted by revharde30

i got a g60 and im putting a motor in it and i want the cool sound

corrado G60? with a G Lader supercharger there is no need for a blow off valve...come on man...thats just silly

[revharde30]

yea

[gotKRAUT]

moved to forced induction forum as it was not E30 specific

[///M Power]

Originally Posted by gotKRAUT

..blow off valves don't function as well as recircs on turbo/centrifugal superchargers but they "sound cool"

Not true at all. Venting to atmosphere or recirculating should be based on whether its a blow through or pull through forced induced setups.

[gotKRAUT]

it really shouldn't matter, its better to keep as much air circulating through the turbo as possible to keep it spooling, where as with a BOV you are just venting the boost air to atmosphere and not sending it back through the turbo...what am i missing?

[gotKRAUT]

After re-reading what you said, I figured out what you meant. As far as AF mixtures and what not go, you are correct. In a draw through setup you should run a recirc as the computer has already calculated for that much Air/Fuel. Although, I'm starting to think you miss understand the purpose of the recirc....

First there were recirc valves. BOV's came way later because they sound cool. In all reality, regardless of draw through or blow through (I'm guessing you mean MAF location) you will still keep the turbo spooling faster if you take the boost pressure from between the throttle body and turbo, and put it back before the turbo. The turbo will continue spinning faster and for longer than if you were to just take that boost pressure and release it to atmosphere.

Granted, a BOV is better than nothing...as that throttle closes, the pressure builds until the turbo stops or even back spools which = teh bad...

Conclusion: Recirc > BOV > Nothing

[triggrhaapi]

Originally Posted by ///M Power

Not true at all. Venting to atmosphere or recirculating should be based on whether its a blow through or pull through forced induced setups.

Uhh... no. The way it affects backspooling is the same either way. I believe you are referring to a common tuning issue whereby blowing to atmosphere causes certain tuning setups to go rich when venting to atmo and using a draw through (not pull through) MAF system. This happens because air is drawn through the MAF and metered, which adjusts the fuel injector duty cycle and provides fuel to mix with air that ends up getting wasted to atmosphere.

[94BMW325i]

with your corrado G60 do you plan on rebuilding the supercharger a lot? With the supercharger you can get the cool whiiiiiiinnne sound, ive heard a bunch of vw's with superchargers, mainly 2 liter 8v's though.

[gotKRAUT]

Originally Posted by triggrhaapi

Uhh... no. The way it affects backspooling is the same either way. I believe you are referring to a common tuning issue whereby blowing to atmosphere causes certain tuning setups to go rich when venting to atmo and using a draw through (not pull through) MAF system. This happens because air is drawn through the MAF and metered, which adjusts the fuel injector duty cycle and provides fuel to mix with air that ends up getting wasted to atmosphere.

Thanks for giving the same answer i gave...

Originally Posted by 94BMW325i

with your corrado G60 do you plan on rebuilding the supercharger a lot? With the supercharger you can get the cool whiiiiiiinnne sound, ive heard a bunch of vw's with superchargers, mainly 2 liter 8v's though.

the GLader already makes that sound a little bit...swap out the GLader for a bahn brenner twin screw...that setup sounds MONEY....loudest SC evAr...so hawt...