The new engine is better in virtually every way and?it?s less small. Called the Global V-6 by GM, the CTS? new 3.6-liter engine is overstuffed with buzzworthy technostuff. A full 60 degrees of space lies between the two banks of cylinders. The block is cast in aluminum. The DOHC cylinder heads use chain-driven camshafts to control four valves per cylinder and each cam is controlled by a continuously variable phasing system resulting in variable valve timing. Feeding those heads is a plastic intake manifold with a two-stage variable-volume plenum, and the throttle is electronically controlled. Throw in a bunch of other tweaks and the result is 255 horsepower at 6200 rpm and 250 pound-feet of peak torque at 2800 rpm.