INDIANAPOLIS — Helio Castroneves felt an immediate difference — a subtle but noticeable uptick in speed — the first time he utilized the boost of horsepower offered by IndyCar's novel hybrid engines around the imposing oval of Indianapolis Motor Speedway.
The question now facing the four-time Indianapolis 500 winner, along with the rest of the drivers on the 33-car starting grid for the 109th running on Sunday, is how best to capitalize on the hybrid over 200 laps spent entirely on edge.
Empty it entirely and then wait for it to recharge, which might take several laps? Save it for short bursts for passes or to defend? Perhaps use it slowly to run down the leader or build a big advantage once out front?
''There is so much more that goes into this than I think people realize or recognize,'' acknowledged Indy 500 veteran Graham Rahal, whose father Bobby Rahal won the 1986 race. ''It's an interesting thing. I mean, the hybrid, it's quite powerful here. On a single lap if you utilize it correctly, it does make a hell of a difference in lap time or lap speed.''
The genesis of the hybridization began years ago, when IndyCar manufacturers Chevrolet and Honda wanted to better align their racing programs with a shift in consumer demand toward hybrid and electric vehicles. But the project was beset by delays as engineers struggled to fit a bespoke hybrid unit into the IndyCar chassis designed more than a decade ago, and that had to meet certain requirements for weight and safety, among other things.
The result was finally unveiled before last year's Indy 500, a design based around ultracapacitors rather than heavy batteries. It provides a quick boost to the existing 2.2-liter, twin-turbocharged V-6 engines before recharging to be used again.
The system was introduced at Mid-Ohio midway through last year's IndyCar season and has been in use ever since.
But it has never been used somewhere like Indianapolis Motor Speedway, where speeds at the end of each straight can hit 240 mph, and the difference between winning and losing can be measured in thousandths of a second.