what is this what do you get from it and advantages dis advantages please also what would i need to have one if wanted

 

Noise, noise, no advantages, noise and external wastegate.

Because of the set up of a standard Impreza turbo, screamer pipes cant be fitted. The exhaust gasses and wastegate vent into the downpipe. To have a screamer pipe, they both need to split, ie, exhaust gasses left and wastegate righ, with a gasket separating the. The exhaust gasses would then carry on to the downpipe and wastegate would vent to atmosphere

 

so you dont gain or lose anything its purley for noise and what is an external wastegate how is it different to how it normally works

 

All std Subaru turbos have an in-built wastegate.... IIRC

Large Garrett turbos don't, so need an external device to control boost. Just a matter of cost really, less pipework and easier to mass produce.

HTH

dunx

 

Even then theres no good reason not to route the gasses back into the exhaust... 'Screamer pipes' are 2Fast 2Furious tuning of the worst sort..... Very American/Veilside.