Well, here is a comparison with an E30 M3 that is much closer to the street car. The 1987 FIA Group A car is less powerful than the E30 DTM car and even closer to the E30 M3 street car. Additionally, Mid-Ohio is a larger race track than the tighter Hockenheim that gives an edge to power meaning the straightaways favor much more powerful F80 M3.
Before we get into which car excels where on this racetrack we want to highlight the difference in powertrains here. The E30 M3 has a four-cylinder which was developed specifically for FIA and DTM racing. The four-cylinder offered higher revs than BMW's inline-6's at the time and sitting further back in the chassis it offered better balance. The S14 as it is fondly remembered was developed by the same man responsible for BMW's insane 1500+ horsepower turbo four cylinder engine era:
"The engine was a highlight. Although there was an internal push to use one of BMW's signature inline-sixes, M technical director Paul Rosche, the mad genius behind BMW's 1400-hp, four-cylinder Formula 1 engines, wanted the balance and high-rpm stability of a twin-cam four. To make the first prototype, he literally sawed two cylinders from the head of an M88—the 24-valve six from the M1 supercar—and paired it with a version of the iron block used in the 2002tii. (Fun facts: The F1 project started with that same block, and Rosche was later responsible for the McLaren F1's V-12.) Test engines vibrated themselves to pieces but produced around 200 hp and more than 7000 rpm."
So in the F80 M3 you have modern BMW M power with forced air providing close to 500 horses and in the 1987 E30 M3 Group A car you have an S14 four-cylinder spinning to around ~8000 rpm with roughly 320 horses. The later DTM cars had more displacement and revved to roughly ~10000 rpm with 340+ horsepower. The DTM car obviously offers a bit more power, torque, and tighter gearing.
The weight difference between the two cars is about 1400 pounds which is night and day. So how does this play out?
The F80 M3 dominates the straights and the E30 M3 dominates the twisties. The end result is practically a wash with the F80 M3 coming ahead by three tenths thanks to its shift speed and straightaway advantage. The comparison plays out exactly as it should. The new car is more powerful and technologically advanced but the track oriented E30 M3 is still more than a match on the roadcourse.
Very different M cars but it is certainly interesting to see the past and present compared: