Go Fast Bits Mk7 GTI Diverter Valve + Blow Off Valve
Make sure to grab an extended 5mm allen or you are going to be really frustrated trying to get the bottom side bolt in and out. This is installed on my Mk7 Golf R but it is actually designed for the GTI model. The R design has an elbow in it to make it fit better next to the intake piping but there is not really any reason to spend another 100 bucks on that version unless you are one of those perfectionists. The hardest part is getting it on because of the snug fit but after its in there is no rubbing. It honestly fits perfectly. The throttle response was an awesome change for me combined with the nuespeed power module installed. The power is a bit more linear and you can feel that the boost is holding much.much stronger under full acceleration. Easy install and worth the price if buying the GTI version.