Get inside an engine and test your mechanical smarts and reaction time. In this game from Popular Mechanics and GameSalad, you trigger the spark that keep pistons pumping.

While you play, you can watch the cylinders run through the combustion cycle. To make it harder, turn off the SPARK GUIDES, and rely purely on your mechanical know-how for timing.

The goal of the game is to push for the highest rpm and drive as far as possible before your fuel runs out. Players start with a simple one-cylinder engine, the kind you'd find in a lawnmower. Do well, and you'll unlock the two-cylinder engine. The hardest level is a four-cylinder finger frenzy!

This game first appeared in the September issue of Popular Mechanics on the iPad. (Check us out in the App Store.)