Anyone guide me in the right direction as to which spring I need to have in to stop the fluttering at lower boost?

 

How many pounds of boost are you running? I have mine set at 20.5 and I still have the original spring in it. If yours is VTA that might be minor compressor surge.

 

I've got mine at 21psi with the original spring and its fine aswell.

 

I had some issues with low pressure fluttering with the blue spring, but had compressor surge with the red spring. Right now I have the blue spring with 2 shims and I still have slight surge. When I get a chance I'm going to try the blue with 1 shim. This is all running 20-21 psi on the stock 16G.

-Paul

 

thanks .... I tried the blue and major fluttering at low boost not even 20 psi. I now changed to the red and still issues.

 

What mods do you have on your car? That will let me tell you what spring color you need to use.

 

I had the same issues as you with my forge BOV, and I wouldn't call myself and expert on this matter but i have tried literally every setting you can play with on this valve. I am at 24psi peak, settling to 22 and the original spring i had in mine was blue. But i had some stalling issues because of VTA and i had flutter too. The red spring is stiffer, more prone to flutter. don't run this spring unless you're at like 30 psi, because its way to stiff. I am currently running the yellow spring in mine along with 1 shim. This setting is about the softest i can go without leaking boost. Because of the softer spring, there is no surge, and on/off throttle transitions are smooth without surge. The blow-off sound is also longer, as opposed to the stiffer spring where it closes back up really fast like "pshht-" mine is more like "psssshhhh" lol Try this out, lemme know what you think. Also the shim seemed to change the sound pitch a bit and it sounds really cool.

 

I had Piper Cams, Helix Turbo back, HKS RS intake , UR Cam gears, and dynoflash. I changed out the helix catback for an HKS and changed the intercooler to Injen. I also installed the upper and lower pipes and the new Injen intake. That is when I added the Forge BOV. I tried the Blue, and Red. It would open up really early with the Blue and not at early enough with the red as it was hitting my turbo. I then put the yellow with one shim then two. I still had some flutter. I then put the stock BOV back and seems better than the Forge. I think I threw off the tune by changing up the air flow. I was told by AL that this was the BOV I wanted, but I don't know how to adjust it so that I can get it right.

 

bump

 

I have the yellow with 2 shims in it, i only get minor surge below like 5 psi, anywhere above that i get none, i have HKS catback, AMS downpipe, TurboXS intercooler, Greddy Profec B, and a K&N filter(sucks). Im gunna put in another shim or a spring higher and see how it does

 

let me know how it works for you as I am looking for a solution