The results are impressive.
Internal combustion engines have been around for well over a century, and in that time, we've managed to refine them to incredible levels, but there's one thing that we can't engineer against: time. ICE engines work with very tight tolerances, and over time, repetitive starts, stops and heat cycles degrade those tolerances. Cylinder walls start to score, camshafts start to wear out, and valve seals corrode. This all leads to eventual power loss. In this video, a late model Z3M Coupe that's nearly 20 years old is put on the dyno to see if this performance-focused BMW can still produce the goods.
We've seen countless cars produce massive numbers on the dyno with the help of some upgrades, and even the Z3M's sibling, the new BMW Z4 delivers more power than quoted from the factory. But this car's S54 engine, which it shares with the legendary E46 M3, has seen its fair share of abuse. BMW originally quoted the power output of this vehicle at 325 horsepower and 258 lb-ft of torque. That's not bad for a naturally-aspirated inline-six engine. In the video, the car hops on the dyno and completes three runs.
After the runs, the dyno spits out the power figures, and they're more impressive than we thought. After 20 years on the road, this BMW has lost barely any power at all. On the first run, the car made 316 hp; that's only 9 horses down on BMW's original figure. On the second run, the car made an incredible 323 hp; only two down. On the third run, things started heating up, and the car fell back to 316 hp. The torque figures are just as impressive: on all three runs the car made more torque than quoted by the manufacturer, and on its second run made nearly 270 lb-ft of torque, which is 12 lb-ft more than standard. This little experiment just goes to show that taking care of an engine will preserve power.