Measuring and policing boost and HP would be futile. There are too many ways to cheat. Like I said earlier, it would have to be an open class based on displacement and weight. Prepare the cars to GCR safety specs and come up with some formula like 1.6 to 2.5 litre minimum weight is X, 2.6 to 3.0 litre minimum weight is Y, etc. I'm not sure what the exact formula would be, but you get the idea.

Like VW16VRacer states; there are many good cars out there with turbos and the up and coming crowd is really taking to them. Personally, it causes me great pain (and laughter) watching these kids today drag race front wheel drive turbo civics and "drifiting". These are some really well preparred cars with really enthusiastic kids (with money) doing REALLY stupid things with them.

I think it would be cool to do something that keeps high-tech, small bore sports cars on the road courses (where they belong) and off of the drag strip and drift tracks. SCCA could be a really good venue for this.

Just my .02