The two-seat, open-top Radical sports racer is built by Radical Sportscars Ltd. of Peterborough, England, and is powered by Radical's own Powertec engines. Dunlop Motorsports will supply the tires.
"Radical owners at these private clubs and at other racetracks around the country, as well as racers in various prototype series in non-Radicals, are clamoring for a new racing series at the professional level that is affordable, reliable, fair and performance-driven," said Simon Shepard, director for Radical West.
"With Radical and the North American Road Racing Association, we now deliver the ultimate race series."
The series will host 12 events over six weekends, beginning in March at Miller Motorsports Park in Utah and wrapping up in September at the Monticello Motor Club in New York.
The 270-hp Radical SR3 and 460-hp Radical SR8 already compete in one-make series' in Europe, Australia and the Middle East.
The competitor with the highest overall points total in both classes will win a chance to test in an LMP2 car with a leading Le Mans Series team, according to NARRA, the sanctioning body for the SRT Viper Cup and the USGT Championship Series.
The SR3 and SR8 champions will get a paid drive at one of the top United Kingdom circuits with the Radical UK factory team in an SR8. Each single-race winner will be awarded a set of Dunlop tires.
"To expand our offering to include yet another high-profile series, and a prototype series at that, shows the direction NARRA is taking," said NARRA General Manager Rob Morrison. "We are serious about sports car racing and creating spectacular events, and I wouldn't be surprised if that word—prototype—is mentioned again in the near future."
Three of the Radical event weekends will coincide with either SRT or USGT races.
The series is designed to be affordable. A Radical SR3 goes for $115,000 with the higher-powered SR8 running $60,000 more.
Drivers also can lease a car on a race-by-race basis. The arrive-and-drive price, which doesn't include the cost of each event, is set at $8,000 for the SR3 and $11,500 for the SR8. That includes full track-side support, use of the car, one set of new tires and the use of scrubbed tires for a practice session. The cost also doesn't include fuel or extra parts.