July 12, 2013
Historical examples of IndyCar engines on display at Honda World. Click image to enlarge
Six years, 101 races. That’s how long Honda went without a single engine failure during their stint as the sole engine supplier to the IndyCar series from 2006-2011. 101 races: that shakes out to more than 600,000 km at racing speeds without throwing a rod, spinning a flywheel or detonating a valve train.
Honda achieved that consistency with a naturally aspirated, four-camshaft, 32-valve, 3.5L V8 that produced 650 hp and revved to 10,300 rpm. These were not lazy, detuned teddy bear engines, these were angry, stressed-out hulks capable of erupting and tearing themselves free of their chassis mounts should they be poked hard enough.
For 2012, Honda had a new challenge. Not only did two new challengers join the fray (Lotus, who departed quickly and in disgrace from the sport, and Chevrolet, who continue to race), but the engine specs changed. Honda now produces a turbocharged, 24-valve, 2.2L V6 rev-limited to 12,000 rpm and producing between 550 and 700 hp – depending on the series regulations for each round.
Wait, what? “Depending on the series regulations”? Yep. IndyCar alters the boost levels for each circuit in the interests of safety. So at Indianapolis for the 500, the car produced just 550hp, while for the shorter street circuits where speeds are lower, IndyCar allows more boost to assist acceleration.
“Boo, hiss,” say the power fiends, “I want 700 hp at Indy.” Cars are allowed to run higher boost during qualifying at the Indy 500 and regularly post average speeds of more than 360 km/h (225 mph). Those sorts of average speeds are simply too high for race day. Honda engineers have estimated they could easily extract more than 1000 hp from these engines. During the heyday of North American open-wheel racing in the 1990s, Honda’s CART teams were getting well over 900 hp from the engines.