The event, to help publicise this weekend's MotoGP round, saw the pair complete a slow lap of the infield course together before a flat-out drag race from the final turn to the finish line.
Although local star Nicky Hayden, appointed as Marshall for the event, declared the race "a tie" - footage clearly showed Pedrosa crossed the famous yard of bricks first.
"It was super fun. I enjoyed it very much," said Pedrosa. "It's always special to do something like this. And actually, I was hearing when we were riding his engine more than mine. But it was very nice when we were together in the straight line and with full speed."It's really cool to do an event like this. It's always a different emotion. I wish one day to try one of these cars, I can see it's very powerful. He is also was wiling to try the MotoGP bike, so maybe one day we can change."
Andretti, who has three Indy 500 podiums to his name, added: "Yes, that was fun! You can see that the car has more grip on the corners because of the aerodynamics, but in the straight... the mid-range of the bike is unbelievable."
"I have a Honda Repsol, the street version of the Repsol CBR, but I'm nowhere near as fast as these guys."
Andretti's IndyCar is powered by a 700bhp, turbocharged 2.2 litre V6 engine and weighs 715kg. Pedrosa's RC213V boasts over 240bhp from its 1 litre V4 engine and a weight of 158kg.
Marco, the son of Michael and grandson of Mario Andretti, currently lies seventh in the IndyCar Series standings while Pedrosa is a double MotoGP winner at Indianapolis.
