This is the hybrid unit i put in my car

It Piggybacks the ECU and uses all the standard sensors and solenoids and even has a built in boost cut lifter

Bargain for$160 new

http://cgi.ebay.com.au/hybrid-WRX-el...QQcmdZViewItem

It is designed specifically for WRX only, but i managed to get it working on my RS


Originally I used to hit max boost of 12psi on a vf12 turbo at 3300rpm

Using this EBC, I can hit 12psi at 2800rpm now.