forge bpv ??

[cjms3]

spring plus 2 shims for stock accept cobb intake or?

[Cue]

Not too sure about the MS3/6's, but on the CX-7, the yellow (which I shortened for less tension) gave me pretty much identical boost numbers as the blue spring.

Yellow IMO.

These are straight off of SB logs on a CX-7.

[cjms3]

anyone else share on the ms3? thanks for the post cue

[AutoEuphoria]

I always heard blue spring + 2 shims...but lately I've been hearing yellow. I'd try them both and see what you get.

EDIT: from another thread


The psi tatings on the forge site are estimates ONLY. If you tesr the spring rates you will find that the yellow is axtually much weaker than our OEM valve. Use that and you just downgraded. Blue comes oit out to be anout he same as stock and shims only make it better. You guys are missing the whole point of upgrading the bpv if you are keeping it set so soft. You gain nothing that way. The ideal BPV settin is a stiff as you can go without surging. You cant base it on just your psi either. It varys on your mods. Mostly stock with 20psi the red spring made me surge a lot. Now well modded i run the red spring AND a shim at 18psi all day long. No surge. My outlook is if you dont run atleast the blue spring you may as well stay stock.
For those who dont know i do all of forge's prototype work for the ms3. I helped develop and test all of the valves for us. I also have other projects going with them right now.

[cjms3]

sweet blue it is

[mo08ms3]

sweet blue it is

Blue with no shims should be good for your setup, but as mentioned ... try yellow/2, blue/0, blue/1, and blue/2 and see which one feels best for your car.

[Cue]

On a stock CX-7, QM times are about 15.7. Since the standback, I've been spending tons of time tuning (with the blue spring) and I've topped my times at 14.59 (just bolt-ons; see sig). After about 2 weeks, the whole spring debate came up on another forum and I decided to switch for the sake of testing. Still ran same times.... I'm telling you... (on a CX7 anyway) the yellow made no difference in performance for me. Just got way less flutter... and I trimmed down the yellow spring for less tension....