Racecar Build: STL RX-7

Mike Van Steenburg pulled an ITS RX-7 out of mothballs to run Street Touring Lite at the 2015 SCCA National Championship Runoffs.

One of the beautiful things about a class like Street Touring Lite, where the rules are broadly defined such that almost any car that meets the engine rules – under 2.0 liters of displacement, is that it’s fairly easy to fit anything into the class.

Mike Van Steenburg has a 1600 Miata built for competition in the class. But when it came time to race at Daytona International Speedway for the SCCA National Championship Runoffs, Van Steenburg didn’t think the 1600 Miata was going to work against the competition on Daytona’s long straights. So he decided an RX-7 would be a better choice for the class at Daytona. When he went looking for one, he didn’t have to look far.

“This car was a customer’s of mine that I built probably 15 years ago,” Van Steenburg explains. “I called him up and said, ‘Can I borrow your car?’ because it’s been in my shop in storage forever. He said go ahead.”

The second-generation RX-7 GTU was originally built for Improved Touring S. As it turns out, a car built for that Regional-only class, in many cases, can slot right into STL with minimal changes. Originally built with endurance races in mind with stiffer springs, Bilstein shocks, and swaybar and bushings built by Van Steenburg’s ISC Racing Services, there wasn’t a whole lot to be done to get the car into shape for STL.

“STL is not a big deal,” he says. “Lightening it up is the big thing, taking all the weight out of it. We put a MoTeC computer in it and changed the intake, because we can eliminate the airflow meter. That’s pretty much it.”

Even then he knew a car that was almost eligible for vintage competition was going to be facing an uphill battle against the newer cars in the class, especially at a track like Daytona where horsepower is king. And it was – Van Steenburg qualified 13th, the fastest of the RX-7s. “We’re at 185, and they’ve got 215-plus,” he says.

“It’s a good car. It’s just slow on the banking,” he explains. “There’s nothing we can do about that. At [Daytona] it’s all about horsepower and aerodynamics. It’s got good aerodynamics, but it doesn’t have the horsepower. The 1600 that I run in STL at the Majors will be a good car for next year at Runoffs at Mid-Ohio.”