Is anyone using a blow off valve? If so what kind. I am kind of interested in the one's that make the whistle & not the whoosh. Any info would be greatly appreciated.
The whistle or chirping style I believe are the HKS SSQV ones. I had one and recently changed over two a 55mm Tial BOV. I really like the Tial in my opinion its a better piece.View attachment 4846
I had a blitz free air bov. It was real loud woosh. So I removed the cone and made an adapter to fit a 1 1/4" hose. Then I attached it to the cross tube right before the turbo. This made it a recircling bov. Then, like magic. The noise was about 90% gone.
I was told that when I did this it gave me more power because the bov air pushing into the front of the turbo forced the turbo to spool and create less drag time on the turbo between shifting. I don't know how true that was. Or if anyone has dyno specs on this. But I liked the fact that I could turn up the boost and not have to worry about the back pressure back spooling the turbo or building up too much pressure and blowing a hose off.
A good basic upgrade is the Talon/Eclipse valves from the 1990-1994 models. With some basic modifications they will hold 25psi, and make a whoosh noise, not some annoying whistle. After that, I'm a huge fan of the Tial products.