While many automakers are developing turbocharged four-cylinder engines to replace the traditional V6, the RDX has gone the other way: Rather than refine the turbo four that powered the old RDX, Acura has ditched it in favor of their venerable 3.5 liter V6. The new engine develops 273 horsepower and 251 lb-ft of torque, versus 240 hp and a 260 lb-ft for the old turbo four, but gas milage improves significantly to 19 MPG city/27 MPG highway for the all-wheel-drive version and an even better 20/28 with front-wheel-drive. The improvements come courtesy of a new 6-speed automatic transmission and the Variable Cylinder Management system, which can run the engine on 3, 4, or 6 cylinders depending on power demands. VCM operation is completely undetectable, so we'll have to take Acura's word that they're not just making it up.
Acura has abandoned the old RDX's sporting pretensions; the new RDX has been tuned for a smooth, comfortable ride, and from behind the wheel it feels big, tall and substantial. The RDX is once again offered with front- or all-wheel-drive, although the latter is a relatively simple system that shifts power to the rear wheels when the front ones slip; it works well enough, but it doesn't deliver the handling magic of the fancy Super Handling All-Wheel-Drive (SH-AWD) system used in the TL and the old RDX. Not that the new RDX is a bad handler; it still responds promptly when you tug at the wheel, but the sports car feel of the old RDX is gone, although I for one don't miss it much. The new RSX is quiet by Honda standards, although ex-Lexus owners might still find it a bit too noisy.