RomRaider

I am just trying to find out if i have my BOV/BPV spring set too tight, every now and then i hear a ch,ch woosh instead of a clean woooosh you normally get when its venting.

Is this becasue the spring is too tight, it seems to happen More when its coming off slight boost. (about 3-5psi) but it also happens on full boost now and then.

I'm only just started running a CAI so i probably didn't hear it before.

Does any one have one of these or can someone post a link to what turbo flutter sounds like, i want to make sure is venting properly and the turbo isn't fluttering.

I have a GFB response(can go bewteen atmo and plumb back via a dial) http://www.gfb.com.au/products?page=sho ... ory_id=445

I have it set to about half as tight as it can go and fully plumb back (no vent to atmo), i had it much tighter but have taken off 4 full turns of screw.

From your description it seems that you've got surge when you lift off the throttle. It's not harmful so don't panic - the surge that kills turbos is when you're at full throttle. With the throttle closed, there's no exhaust powering the turbine, so the compressor just slows down when it surges.

Loosening the spring will probably help.

But if you are VTA at all, you have to be careful about loosening the spring to the point where the valve opens up at idle. With VTA, that's a leak and it will screw up your AFR.

If you have it on full recirc, you can loosen it a lot. Since the vent side is connected to metered airflow, it doesn't matter if it opens at idle.

Thanks,

I Losened the valve almost as far as it goes and the noise was actually happening more i think, so i'm back to the spring tension i was before. I was running vent to atmo before but the BOV noise through the air intake is so loud now there is now point anymore really.