Installation of an HKS bov is pretty straight forward. I purchased the bov from the local classifieds, new in box. I think I got ripped off, having found the same product on ebay for 65$. I paid 130$ or something. The kit also wasn't WRX specific, so I had to buy an adapter separately.
The Blow Off Valve itself
This filter is suppose to be installed, but it is garbage. Just toss it into the nearest pile of **** as it'll only cause you pain and break. I'm surprised they give this to you. Using this filter, you'd need extra vacuum hose as they do not supply you with any. If you do not use this filter, you don't need extra vacuum hose.
The WRX specific adapter.
This is the stock by-pass system. Two 12mm bolts hold it in place, connected to the intercooler. A vacuum line connecting to the throttle body and underneath (not visible) is the recirculation hose connected to the turbo inlet.
Copyright (c) 2015 project-build.net. All rights reserved.