The 2013 Amsoil Engine Masters Challenge is underway with dyno testing being conducted at the University of Northwestern Ohio. Early results can be found at the PHR website and on YouTube. Up to 10 teams a day can be tested as the engine builders try to qualify for the finals.

A variety of engines were showcased on Day 2, including the 451ci Mopar of SKMFX Engines (676 horsepower), a 572ci big-block Ford from Freelander Race Engines/Oakley Motorsports (870 horsepower) and a 404ci Buick from Automotive Machine Performance (649 horsepower). The eventual winner will not be based on total horsepower, but rather there is a points formula that factors in engine displacement so different-sized engines can compete against each other.

The videos included here provide interviews from Day 1 (below) where a 428ci Pontiac from Throttle’s Performance ripped off a 738-horsepower run. The team from Henderson Power Sports also posted a behind-the-scenes look at their efforts (above). You can see the countdown clock that lets the team know just how time is left during each test opportunity — which certainly increases the pressure on all the teams. But then when the engine suddenly doesn’t fire — well, you can watch what happens. The team eventually pulled 698 horsepower on their 407ci small-block Chevy.

Some of the top teams from previous challenges have yet to compete, including last year’s winner School of Automotive Machinists.