It's often said that BMW's advertised horsepower is usually less than the real deal. It's been seen in models such as the humdrum 328i from nearly a decade ago, all the way to the all-new M4. It even applies to cars with BMW engines, such as the turbocharged straight-six in the current Supra.
However, does the same train of thought still apply in neoclassic BMWs? Has time been kind to these engines and still deliver the numbers? It's time to take one of these old Bimmers out on the dyno. In this case, it's a late 2001 (or very early 2002) Z3M Coupe. This particular Z3M Coupe is owned by the folks at Evolve Automotive.
If the name sounds familiar, Evolve Automotive is the tuning firm that squeezed out 1,000 bhp from an F90 M5. As for this Z3M Coupe, it's still mostly stock. The only parts that Evolve changed are the headers and exhaust, along with a quicker steering rack that shouldn't affect the final dyno figures. Even with new pipes, it shouldn't be much of a jump from stock, right?
As for the engine, the Z3M came with an uprated 3.2-litre, straight-six. Dubbed the S54B32, this Euro-spec car packs a bigger punch compared to the ones sold in the US. The result is 321 bhp (239 kilowatts) and 258 pound-feet (350 Newton-metres) of torque. For reference, the US version put out 315 bhp (235 kilowatts) and 251 pound-feet (340 Newton-metres) of torque.
Irman from Evolve Automotive in the UK reckons that the engine is pretty strong and healthy. Of course, that's according to his butt dyno. A real dyno test should reveal the truth, and the numbers. So, what are the results? Let's just say Irman was right on the money about the car's performance.
Even if you factor in the exhaust and headers, the figures from the three runs raise a few eyebrows. We won't spoil everything for you, but let's just say it's still pretty close to the advertised horsepower. Of course, results will vary from car to car, but the test also shows that a well-cared M engine still keeps a lot of its horses in its stable.