Running more boost? Get rid of that leaking POS dump valve...

[Jason]

Hey Guys,
I have been trying to find what I thought sounded like a boost leak for a while. I thought it was at the manifold inlet, then I was thinking I blew out the gasket at the head. I finnaly found it to be the boost dump valve. I had originally plugged the outlet and it was ok. As time has gone on, it seemed like the turbo didn't spool as well and there was a different sound from the engine off boost. Rather than the nice whistle is was a whooshing sound. Anway, I found it to be leaking between the valve and manifold, so I siliconed the O-ring and that helped a bunch, but there was still noise. Upon closer inspection, it was leaking boost from the seam where it is assembled. I decided to remove it and installed a 1.5" rubber plumbing cap with clamp that I got from home depot. WOW what a difference. The turbo spools better than it ever has, and actually isn't too bad at all even with the large .63 a/r hot side I still have. This would be one of the first things I would remove if you plan to run more than stock boost!

Jason