I've had my car teched and passed with this regulator system on...[/b]
You talking about your annual inspection, or did you get protested? If the former, that check has ZERO credibility (or supportability in a protest situation) as to the legality if items on the car; that's an annual safety check only.

If you want de facto and de jure proof of legality of a mod you've made, you need to follow the process specified in GCR 8.1.4 (p GCR 65 in the latest version). Otherwise, its legality is still up to argument.

Personally, as I noted above, I believe it can be done legally, and I'm sure the board here would be tickled pink to get into debating its legality. However, given your circumspect discussion of this "system" you've installed, I'm guessing you want to keep it proprietary; ergo you should make any potential customers aware that they are proceeding at their own risk.

Greg