I talked to the guy earlier in the night and he explained his set up to me this way: The larger turbo has significant lag and comes on pretty hard. The supercharger in front of it was able to spool the turbo up at 1700rpms. I didn't see if he had some type of butterfly system to bypass the supercharger at some point but the s/c was running a magnetic clutch like an air-conditioner compressor to turn on and off as needed by the supercharger. More amazing was the packaging. Very impressive and definitely not budget limited based on what I saw. However, and this is the part that most of ricer crowd don't get, Why spend $15K on a $30K car and push an engine/tranny combo to the ultimate limit to get times that a GT can do for $4K on top of $21K and last 100,000 miles. Sort of stupid and pointless in my opinion. Yes it makes it faster than all the other little 4 cylinder cars but the reality is that 101mph in the quarter is not all that great for that much money. There is no substitute for cubic horsepower.
I will also tell you that on a road track, I not only ran the WRX's down the straight but ran with them in the corners and I'm still working on my driving skills. As the day went on, I put a race level RX-7 and and Porsche GT into the dirt trying to keep up in the corners so I'm getting some of it down. I'm sending Santa my wheels and tires lists for christmas right now.
When people tell me their 1/4 mile times, I tend to go with a direct comparison on my car on the same night in the same lane. For example, when I ran against a Z06, I ran 13.1 at 110 while he ran a 12.9 at 113. This was impressive and I had a direct comparison. Friday night there were 3 Pontiac GT's running 14.2's at 98 mph which I think was the best I saw. Another direct comparison. So now if someone tells me how fast their cars are, I try to compare it against what I saw the same night I ran. Sort of kills the BS factor since I know what my car runs with the dyno numbers I last saw and the weight of the car is know.