The High Value engine family from General Motors is a group of cam-in-block or "overhead valve" V6 engines. They use the same 60° vee bank as the 60° V6 family they are based on, but the new 99 mm (3.90 in) bore required offsetting the bores by 1.5 mm (0.059 in) away from the engine centerline. These engines (aside from the LX9) are the first cam in block engines to implement variable valve timing, and won the 2006 Breakthrough Award from Popular Mechanics for this innovation. For the 2007 model year, the 3900 engine features optional displacement on demand or "Active Fuel Management" which deactivates a bank of cylinders under light load to increase highway fuel economy. It was rumored GM would produce a 3-valve design, but that never came to be. These engines were produced primarily at t