E60525d

kempower sent me the following graph of a owner with a 2004 525d who got it dynoed. the car was standard and it produced 188bhp at lower RPM and more torque. why is this?

bmw claims:
177bhp@4000rpm
400nm@2000rpm

E60525d

so no engine experts here???

E60525d

some one help me???? are other BMW's overpowered aswell?

CRRobert

I try and take a guess. I would imagine that due to manufacturers tolerances, that there are some that vary in their numbers, and they chose the low one. People are happier if it is higher than what is stated, than if it is lower. Just look at what the new Mazda RX-8 went through. They claimed a higher horsepower(at least in the US) than what owners were getting, and now offering to buy back there cars.

Another though just could be the conditions of the dyno test. I read a previous website that talked about how you could alter the results of the dyno test by varying the conditions. They were able to increase horsepower and torque by using a big fan in front of the vehicle blowing air while it was on the dyno.

I would imagine that their are also differences between dyno's themselves which could result in the difference you see here.

One other possibility, is that BMW finds the horsepower and torque at the flywheel and then calculates losses through the drivetrain to get at a rear wheel horsepower and torque. Could have over calculated the losses.

This is my opinion on these, and if someone has facts, feel free straighten me out.