So I was lucky enough to throw my money at
Jason@JacFab and get in on the first production run of the valve, and I've finally had enough time to collect data and really get a feel for what it does for the car.
The most obvious thing initially was what I would call a "smoothing" affect on power delivery. The car just felt better, there wasn't that obvious "oh, here comes the turbo" feel. Throttle response was noticeably improved as well. Once you hammer down, it was pretty obvious the power came in sooner, and was holding more boost longer. Installation was a breeze, and there is even a video for anyone who may need some help. Once installed(one of my favorite parts), the valve is practically invisible. Thats a big perk for you guys under warranty, or perhaps you guys doing any "Mexico" racing! Quality shames the OE part in design, function, and built quality.
This is a highly functioning, well made bolt-on that I would recommend to anyone, tuned or not.
Now:The numbers!!!
Some of you may have seen the test done on a bone stock GM tune
VS bone stock GM tune with JacFab valve. The bone stock tune held more boost, and made more power across the entire powerband as seen with the data in HPTuners.
For those that didn't see that, here it is.