Buy a MAC valve (part number 35A-AAA-DDBA-1BA) and save money for your tune. It cost me about $35 for the valve, a couple fittings, and some vacuum line. I just spliced into the existing BCS harness and soldered on the leads from the MAC valve. Otherwise you'll need to find a pigtail that works with the BCS harness. I didn't feel like spending the time or money tracking one down. Used double sided tape to stick it to the existing BCS bracket and put a zip tie around it for security. The MAC valve is the same one used by a variety of performance parts manufacturers. It is working great for me so far on the e-tune that I'm getting right now. REMEMBER: YOU WILL NEED A TUNE! Otherwise you'll overboost since the wastegate duty cycle must be lowered quite a bit for a 3 port.
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