[Kolyan2k]

I never paid any attention to dynos etc. So it's basically the first time I actually looked at some. My question is why do 335i w/N55 dyno at 290/315 stock (BMW rated 300/300) and M235i dyno only 295/330 (BMW rated at 320/330). Also when I looked at BMS Stage 1 both dyno 325/360-365.

Am I reading something wrong? I was looking at Burgertuning website. I was under the impression that most BMW engines dyno either the rated stock numbers or more.

[Joe240]

Some Dynos read wheel hp and others estimate the crank hp. The Dynos for Burger that are reading over the BMW numbers are estimated crank numbers. The ones you see that are below BMW numbers (the 290/315 or 295/330) they are wheel hp. Now when you figure a 15% drivetrain lost, that means you're actually above the BMW numbers at the crank (347/388). Since you'd have to remove the motor to measure the actual crank horsepower, those numbers (the 347/388) are estimates assuming the 15% drivetrain loss.

Also, the 235/240 are tuned slightly from the factory to have more power than the 335/340.

[XutvJet]

Most M235 dynos from Dynojets I've seen show 305-310whp and 320-330wtq with the 6MTs showing slightly higher numbers. So around 350-355hp and 370-380tq at the flywheel.

[Kolyan2k]

Yes I understand the crank vs whp. What I don't understand is why 335i dynos almost the same as M235i and Stage 1 both exactly the same on Burger website

[Joe240]

Pretty sure they don't actually dyno the same. I think some sites might claim they do just by testing one because they have the same motor.

[mike@x-ph.com]

Different dynos give you different numbers ... Only way to check power of 2 cars is to get them dyno'd same day on the same dyno