Ok so i have the stage two Hahn turbo kit. Well i dont really like the BOV so i got one from Turbosmart. IT was only $190.00. Well when the car is under alot of pressure then the BOV sounds great but when its only at like 4 PSI and you shift it makes a weired sound. Kind of like a butterfly or something. You can twist the top of the BOV from hard to soft. What does that mean? WHat is hard to soft and will turning it one way make that butterfly sound thingy go away. All i want is a loud sound that more or less says yea its turboed.


THanks guys

JAson

hey dude i have a RFL and mine does that butterfly sound at low boost also . If you adjust your bov to hard , it will just sound more sharply as it exits. If you soften it up, it will just exit softer and a smoother flowing sound but i dont think that you can get away from that butterfly sound . Its going to happen no matter what on low boost. I like the way that sounds and people still go wow when they hear it .

On typical blow-off valve designs, a large valve is utilized in order to accommodate high boost / high horsepower applications. However, these large valves tend to react slowly and require high activation pressure to open, therefore are not able to activate and prevent compressor surge at light-load conditions. So they almost open a little or keep fluttering open and close. If you read about the HKS SSQV it explains about what makes that blow off valve so special. Clicky

I may be wrong. I'm still learning.

The "butterfly" fluttering noise sounds like compressor surge. You might not think so, but I had that noise for ever with my blitz DD. I know the blitz is made with a low and high port, but when I switched to the RFL, I still had the flutter at low boost( under 4 psi). I went ahead and tapped a 1/4" vac line directly into the plenum on my intake manifold and the surge/flutter went away.
It might not my surge, but I wouldn't trust my $700 turbo on that, thats why I added the vac line. BTW, it makes the BOV so much more responsive with it's own dedicated vac source. I also did this with my Tial WG, and it opens so much quicker!(no boost spikes!)








Failure is not failure if you learn from it

compressor surge is bad...mmmmK



I used to race cars, now I race myself.
5K PB: 24:50
10K PB: 54:26