Screamer Pipe

Hia, sorry to be a numpty but... what is a screamer pipe, can anyone explain to the muppet here? what does it do, please dont say it screams! or i will !!

When you have upgraded turbo setup with an external wastegate, a screamer pipe is a pipe that vents excess exhaust gas from the wastegate straight to atmosphere. The alternative is to have it vent this gas back in to the exhaust like the standard one does. They are called screamer pipes because they are very loud (as they are effectively unsilenced exhausts).

Thanks great, thanks. I have an upg on my car (bpu) and it has an external bov. std turbos running about 1.1bar. could i do this to mine now and how/which pipe etc. how could i do this or do i need a specialist to do it?

No the std turbos have internal waste gates so you can't.

You'll need an external waste gate to have a screamer pipe

what benefits do you get from a screamer? (over say, a re-circ dump valve)

Screamer pipe and dump valve are two competely different things, screamer pipe dumps hot exhaust gasses, dump valve vent air trapped in the clean air to engine inlet side.

Screamer Pipes are adventageous if you are reducing your back pressure under boost to the bare minimum.

And yeah they are nothing to do with the dump valve. They are post turbo parallel to the exhaust....they bypass the turbo when you don't want more exhaust gas going throught the turbine (ie when you've hit full boost)

Basically if your exhaust past the point where your external wastegate would join in is not big enough you gain by diverting some of the exhaust gas so it doesn't go through the exhaust. Also introducing the exhaust gas from the wastegate into the main exhaust stream can cause turbulence where it joins, which reduces the efficiency of the exhaust.

Also some people like the noise they make, and not plumbing it back into the exhaust is a lot easier from a fabricating pipework point of view.