[brad65ford]

Did a search couldn't find anything but its got to be wondered or asked before. Currently I only have a stage 1 tune and mid pipes and I'm wondering how accurate the hp and tq really is in each gear in the sports display mode. Also I noticed I achieved the same hp in 3rd and 4th which seems straight since the gearing is different. Very confused at that making me think its not accurate. All in all its stating in 3rd I'm seeing around 540HP, again no clue how true this really is.

[Thescout13]

It's not accurate at all. It's a gimmick.

Just search "sport displays" and a ton of threads come up:


Sport Display - Power/Torque? https://f87.bimmerpost.com/forums/sh....php?t=1466015

[Chopper731]

I’d guess it’s reasonably accurate with everything stock. That probably goes out the window once modifications are mixed in, though.

[Anthony1s]

I have bootmod3 tune on my N55 M2, which updates the gauges. The few times I've used the gauges, they seem fairly accurate to the peak power ratings others have dyno'd. However, I can't remember if the readings on the sport displays were engine or wheel power. You can estimate power fairly accurately using torque and rpm (tq x rpm / 5252) or MAF sensor readings (~10hp per one lb/min), so I don't see why BMW would make up some gimmick thing for something that can be easily calculated.

That being said, the sport displays only display current and peak power. They don't plot a graph like a dyno session would. So all I can gauge their accuracy on is peak power compared to other dyno readings.

[doughboy]

Originally Posted by brad65ford

Did a search couldn't find anything but its got to be wondered or asked before. Currently I only have a stage 1 tune and mid pipes and I'm wondering how accurate the hp and tq really is in each gear in the sports display mode. Also I noticed I achieved the same hp in 3rd and 4th which seems straight since the gearing is different. Very confused at that making me think its not accurate. All in all its stating in 3rd I'm seeing around 540HP, again no clue how true this really is.

Actual wheel HP is unaffected by gearing, but it does affect dyno results due to how dynos work.

Bear in mind though these gauges are supposed crank figures. So you wouldn't expect any changes due to gearing in any case.

Its very unlikely to be a measured quantity it's just taken from a map table of output figures from the factory. That's why you have to adjust it when you tune.

The car (any car) has no direct means of measuring it's own torque output. So it's either approximated from rate of acceleration and vehicle mass or a map of engine data.