Dyno Tested: BMW's past and present turbo sixes

BMW has always had a gem of an inline-six on its hands, regardless of which particular powerplant you're referring to. But over the last couple of years, it's the German automaker's turbocharged 3.0-liter N54 engines that have been lighting enthusiasts hearts afire, and steering more than a few buyers away from the M3 and into the seat of a 335i. And when the N54 proliferated across the rest of the automaker's lineup, it was well-received in nearly every application.

For 2011, though, there's a new engine in town, and the big question is whether or not the single-turbo N55 is better than the previous twin-turbo N54 or, at the very least, not worse. Helping shed some light on the matter is the crew from Automobile Magazine, who managed to snag a trio of various N54-powered 3-Series' – one of which was the hotted-up 2011 335is, which uses a high-output version of the old N54 – along with one new model powered by an N55.

And the results? Well, it's pretty much more of the same: good peak horsepower (266 horses) and a nicely flat mid-heavy torque curve, cresting at a stout 302 pound-feet. But we'd be remiss if we didn't point out that the new N55, while seemingly offering less turbo lag than its predecessor, appears to be a wee bit less powerful overall than the N54. Progress?

Photos by Zach Bowman / Copyright ©2010 AOL

[Source: Automobile Magazine]