why do turbo's utilize a b.o.v. while sc utilize a bypass valve what's the differance besides the bypass valve recirculating the air back through the system causing a cooling effect? I know that the bov vents the air charge to the atmosphere....wouldn't the turbo guys want that air recirculating? S h i t is not making sense to me.
No expert here but this is the way I understand it. Turbos keep on building boost, which could get much higher than you want or need. The blow off valve regulates the boost. The bypass valve is for when there is a sudden spike in pressure in the inlet tube, like when the throttle is closed quickly. Instead of the intake charge blowing off the inlet tube from the throttle body or something like that, it lets the pressure off. I'm not sure why the bypass needs to be routed so it recircluates though. Dave
1st, let me say that some turbos use bypass valves, such as the one on my car. There was a guy that did alot of bypass valve/bov research that documented all the little details on his eagle talon... Anyways, after all was said and done, there was no gain in performance from using one or the other. Its really just a matter of if the maf is before the bypass/bov or after. If the sensor is before a bov for instance, your ecu won't understand that it just lost a butt-load of air through a bov and then run super rich. In that case, you would want to run a bypass valve.
