autoevolution
 

70 WHP Separate the E90 and F80 M3 models in Real Life, Says Dyno

When BMW came out with the specs of the new engine fitted on their M3 and M4 models, some people were disappointed to learn that the new plant made just 10 HP extra compared to the retiring one. On the other hand, most rejoiced to learn that the torque numbers went up 40%.
BMW F80 vs E90 M3 Dyno Runs 4 photos
Photo: Motor Trend
BMW F80 M3 Dyno ChartBMW E90 and F80 M3 Dyno ChartBMW E90 M3 Dyno Chart
That is a serious increase but later dyno runs showed that the HP gain was also greater than what the company declared officially. The guys from MotorTrend took the new M3 to a dyno belonging to the guys from K&N and put it to the test. To make things more interesting, they also brought along an E90 M3 to see exactly how big the difference between them is.

The stock numbers look like this:

- E90 M3: 4-liter naturally aspirated S65 V8 engine making 420 HP and 400 Nm (295 lb-ft) of torque
- F80 M3: 3-liter twinturbocharged S55 inline 6-cylinder engine making 431 HP and 550 Nm (406 lb-ft) of torque

Those should be the numbers posted at the flywheel. The wheel readouts should indicate around 13-15% less due to powertrain losses. That means the E90 model should show around 350 WHP and the F80 around 375 WHP.

That’s not what the readout showed though. According to their graph, the E90 M3 posted only 306 WHP and 238 lb-ft (322 Nm) of torque at the wheels, numbers that are simply too low to take into account. From the looks of things, the engine didn’t have enough air to work with at high RPMs and therefore showed drastic power losses. All other dyno runs we’ve seen of S65 units showed at least 330 WHP. At least!

The F80 performed better but was still under par. According to them, it showed 379 HP and 378 lb-ft (512 Nm) of torque at the wheels. Sure, it’s a bit over what BMW claims but earlier runs done by other professionals showed it to have well over 400 HP at the flywheel.

So, it would appear that the two actually have 70 WHP between them and not 10 as the official specs would claim. While it’s all very good potential news for new M3 owners, it’s rather disappointing for those driving older versions.

However, we tend to think there was some sort of mistake involved here. There simply is no way the S65 engine could post such low numbers. Testing the two head to head again seems to become a must.
If you liked the article, please follow us:  Google News icon Google News Youtube Instagram X (Twitter)
 

Would you like AUTOEVOLUTION to send you notifications?

You will only receive our top stories