A look at the support series running this weekend:
The primary feeder series for IndyCar. They're slightly smaller and not quite as powerful (420 horsepower as opposed to 635 for IndyCars) and they run on unleaded gasoline as opposed to the ethanol that IndyCar uses. The series opens its season this weekend in St. Petersburg.
Star Mazda series
An open-wheel series, these cars are another step on the IndyCar ladder, just below Indy Lights, as part of the IRL's "Road to Indy" program. The Mazda engines produce about 250 horsepower. The series opened in Sebring, with Tristan Vautier winning last weekend.
An entry-level open-wheel series which now falls under the sanction of the Indy Racing League. These cars produce about 170 horsepower. Star Mazda is the next step up for these drivers and teams. This is also the opener for this series, which doesn't run again until the weekend of the Indianapolis 500.
SCCA World Challenge
A sportscar series with two classes, Grand Touring and Touring Car. The GTs put out up to 525 horsepower and are versions of stock sedans and coupes. The TCs are smaller, compact or touring-type cars that have about 235-275 horsepower. This is the season opener.
Jim Tomlin, Times staff writer