The BOV and BPV from BNR/Forge comes with two springs. A stock rate spring installed and the yellow (stiffer) spring for higher boost applications needing more holding power. The knurled cap with the boost nipple on it unscrews and you can replace the spring with the Yellow spring. I'm not sure anyone will need the yellow spring until we get a turbo swap pushing more than 22 psi in the car. Sorry I was not around today, went to work at 0700 and just walked in the door at 2300.
Oh, and the car rev limits at 3,000 rpm while the car is not rolling. GM (as well as mosts other auto manufactures) has decided that there is no need to hit the red line revving at a stop. This can be adjusted with custom tuning though.