 Re: Screamer pipe
Don't want to cause an argument here but I'm afraid your wrong Sleeper.
BOV's or dump valves whether recirculating or to atmosphere are there to protect the turbo.
Without one, when you close the throttle there is nowhere for the gas to go, but the turbo is still spinning and trying to make boost. So what happens is that the turbo stalls. Apart from this causing turbo lag on gear changes (the turbo has to spool up again) the inlet vane is pushed hard against the bearing and will cause premature wear.
So the BOV allows the turbo to keep spinning without pressure, so that a quicker response is gained between gear changes.
Again with the screamer pipe (I think people are getting confused because of it's name - so lets call it a waste gate pipe), as I stated in an earlier post, I am referring to an external waste gate and with this set up the waste gate exhaust enters the main exhaust at right angles and therefore must disrupt the exhaust flow. Don't forget, we don't want any back pressure on the turbo exhaust.
Also as I stated before, the fuel system on my car doesn't have a lambda sensor, therefore using a "waste gate" pipe will not have any effect on the fueling.
Perhaps on an internal waste gate turbo and on systems using lambda sensors the previous points posted are a good argument.
So once again (depending on engine set up) I think a separate pipe for the waste gate would increase power and again with it's own silencer.
I'm not interested in noise but power.
John |