Holy shit, that was fun.
Got up to Elkhart Lake yesterday for the second day of the 2009 SCCA June Sprints at Road America along with my uncle. We showed up just as the Formula Atlantics and Formula Mazdas were finishing their second qualifying session, filling the air with a beautiful song of high-revving engines. The GT cars started their second qualifying as we found our way to the stands outside Canada Corner, just in time to watch a GT1 Corvette end the session prematurely by depositing itself in the gravel trap and a trail of fluid right across the racing line — the latter of which collected a 911 (which spun towards the inside of the corner exit but was otherwise unharmed) before the stewards black-flagged the session.
The first race of the day was the 69-strong field of Spec Racer Fords — which must’ve been exciting at T1 on the other corner of the track, but served us just fine at T12. Here’s the front of the pack on the pace lap:

…and the tail, thirty-five rows later, heading up towards T14:

They weren’t shy about passing under green:

We didn’t see any incidents at T12 while we were there, but a multi-car wreck just over the crest of the hill into T6 stopped the SRF race about six laps in, and when it resumed they took only another three laps of racing. We grabbed lunch during the stoppage, and spent the abbreviated lunch hour wandering around the paddock.
One gentleman let me drool over his D Sport Racer at awfully close range. My only regret of the day is that I didn’t take more photos:

Yeah, I want one. The tape over the front of the body might be for drag reduction: Road America is a fast course with a lot of long straights, and this DSR had a 1000cc powerplant. Very clean car, aerodynamically; I wonder if they’re allowed to run dive planes at slower tracks.

Underbody tunnel exits, nearly right up to the lower plane of the rear wing. I believe that’s a lower suspension arm cutting through the left-hand tunnel. Other than the tunnel exits, the rear of the car is pretty open, which I’m sure helps draw air out of the rear wheelwells. (A few of the CSRs had fully-enclosed rear wheels, like the Jaguar Group C cars.) I’m a bit surprised that the underbody doesn’t run under the gearbox.

Between the louvers on the front fenders and the opening at the rear, I don’t think high pressure in the front wheelwells is going to be a problem. I’m guessing that the ledge running around the outside of the sidepods is there to direct air towards the rear wing rather than let it flow over the sides. You can see in the top image how it curves inboard of the rear wheelwells.
A bit later on, after watching the Formula Fords and Formula Continentals tear up the track, we found ourselves at a bar and concession stand called Perl’s with a great view of turns 6, 7, and 8. It was a perfect place to watch the CSR/DSR/S2000 race: from that vantage point, one can watch a driver set up a pass exiting T6, carry momentum through T7, and execute the pass into T8. (I also got a chance to watch the above DSR’s pilot make a pass for position around the outside of T7 — possibly the highlight of the afternoon.)
T6 exit:

We’ll follow these cars down into T8 as the black-and-green DSR completes his pass and the white car’s driver tries to follow him through.
T6-7:

The green and red car is, I believe, a Radical SR3. The programme has them running in CSR, but they were well off the pace at Road America that afternoon. In particular, it seemed like they had a hard time carrying as much speed through T7 as the rest of the CSR/DSR field.
The run up to T8:

That’s a kart track in the background. I was tempted, but the racing was too good to miss. You can see the braking markers for T8 on the wall to the drivers’ right. Notice how much of a gap the black DSR has opened up on the Radical.
T8 apex:

The black DSR is behind that first tree; sorry ’bout that.
There was of course more racing: I got to watch the Formula Atlantic/Formula Mazda race from the outside of T5, which was spectacular but ill-suited to photography. (All of my photos from there are full of chain-link safety fence.) If I make it back to the June Sprints next year, I’ll definitely spend more time taking photos in the paddock and watch most of the races from Perl’s above T7.
All in all, a great way to spend a Sunday.