Whenever a new BMW engine is announced, or a new version of an existing one is added to the model portfolio, it’s tough not to take the output figures with a grain of salt. As we’ve learned with some of the more notable models BMW currently sells, advertised horsepower and torque aren’t always the same as what real-world dynamometer tests reveal. It’s happened with the M5 and its S63 M V8, and more recently with the B58 in the Toyota Supra. We know that BMW engines coming with rather conservative power ratings isn’t exactly news, but the S55 in the M2 CS joining the ranks is.
As per German car magazine Sport Auto, the M2 CS, which comes with an S55 engine producing 444 horsepower at 6,250 rpm, put down the equivalent of 484 horsepower when tested on a dyno. Torque, which is advertised at 406 pound-feet, peaking from 2,350 to 5,500 rpm, was measured at the equivalent of 472 pound-feet. Whether or not the results are repeatable remains to be seen, but casting doubt aside for a moment, the numbers are quite impressive not only for the outgoing S55 engine, but also for a car with the dimensions of the M2.
In today’s turbocharged and direct-injected world, it seems we have entered into a new realm of internal combustion engine tunability. Never before have manufacturers been able to squeeze so much power from such little displacement, while at the same time, versatility among engine lineups has also broadened tremendously. BMW’s S55 M turbocharged inline-six, which is soon to be replaced across the board by the S58, is offered in a rather wide array in terms of output. There’s the version for the M2 CS Racing, which makes anywhere from 275 to 359 brake horsepower depending on configuration and the racing series in which it is to be run, and there’s also the exalted water-injected variant developed specifically for the 2016 M4 GTS, which maxed out at an advertised 493 horsepower and 443 pound-feet of torque.
To put things into perspective, Auto Sport‘s testing of the M2 CS puts it above the M3 and M4 CS, with their paltry 453 horsepower, and within spitting distance of the water-injected S55 of the M4 GTS. That’s quite impressive for BMW’s smallest current M car, which is said to use the same 444-horsepower S55 as the M3 and M4 with the competition package.
With the S55 on its way out and the B58-based S58 on the horizon for the next generation of BMW M cars, the news bodes hopeful for the future of BMW internal combustion engines, however limited it may be.—Alex Tock
[Photos courtesy BMW AG.]