Check out the Speed Channel. It covers quite a few racing series that feature production-based cars, such as the following (in increasing levels of sophistication and speed):
SCCA MX-5 Cup
The SCCA Mazda MX-5 Cup will provide an affordable, entry-level nationwide professional series whereby drivers compete in identically outfitted [2006 Mazda MX-5 Miatas].
Mechanically, all MX-5 Cup cars will remain essentially stock, as delivered from the dealer, with only bolt-on modifications to the intake and exhaust systems. While the stock MX-5 Miata produces 170-hp, it is expected that an MX-5 Cup car will produce in excess of 200-hp. All MX-5 Cup vehicles will be equipped with a six-speed manual transmission and may be run with the optionally available limited-slip rear differential.
(There’s also the
Spec Miata Race Series, that is open to the older Miatas, but I don’t think they get on TV very often.)
The features two classes of cars, both of which run simultaneously in the same races: SCCA Speed World Challenge
Touring Car (TC): Cars up to 2.8-liters that are naturally aspirated are permitted. Forced induction permitted as if it came that way from the factory. The cars can be front-wheel, rear-wheel, or all-wheel drive. The cars must be able to seat four adults, and convertibles are not allowed. Class horsepower range is 225-275 bhp.
TCs include Acura TSX, Audi A4, BMW 325, Ford Focus, Honda Civic, Mazda 6, Mercedes C230, VW Jetta,
Grand Touring (GT): Includes a variety of production displacements with no maximum. Forced induction is permitted and is used to equalize individual models. Sedans, coupes, convertibles and two-seat models are permitted. The cars can be rear-wheel, or all-wheel drive. Class horsepower range is 425-550 bhp.
GT cars include Cadillac CTS-V, Chevrolet Corvette C5 and C6, Dodge Viper, Porsche 911 GT3.
The **Grand American Rolex Sports Car Series ** also has two classes:
The GT division is home to production-based race cars that are similar in appearance to the latest high-performance sports cars and coupes that you see on the street everyday.
Only in GT can you see nimble, flat-six Porsche GT3s take on big-bore V-8 Corvettes and Pontiac GTOs while also mixing it up with three-rotor Mazda RX-8s, mid-engine Ferrari 360s and Maserati and BMW M3 coupes.
The rules for GT employ several methods of equalization including race car weight, tire size and engine rpm limits to provide an even playing field for a variety of international and American-made cars.
Engines in GT machines produce between 390 and 450 horsepower depending on the car, and minimum weights range from 2,500 lbs. to 2,800 lbs. The popular Porsche GT3s and BMW M3s – two championship winning models in GT over the years – weigh-in at 2,600 lbs. while the bigger Corvettes tip the scales at the maximum 2,800 lbs. Top speed for GT race cars is 170 mph.
The other class in GAC is Daytona Prototypes, which are not based on street cars. As in the Speed World Challenge, both classes run in the same races at the same time.
So there’s no shortage of racing with production based cars. BTW, all of these series race on road courses, not ovals.