Originally Posted by Dave07997S
It won't be 450 hp from the factory, according to most recent stories if you read the whole article..same hp as E9X M3 but 100 ft/lbs more tq.
That's a nice story, but it's not possible. Unless BMW uses unbelievably small turbos or the motor redlines at like 5,000RPM, there is no way it can make 395lb/ft and only 420 horsepower.
It's very simple to calculate horsepower at a given RPM if you know how much torque the motor is making at that RPM. If the E80 M3 has a similar torque curve to the F10 M5, and if it makes 400lb/ft of torque at its peak, it would probably drop off fairly significantly by 7,000RPM but even if you are extremely conservative, it should make at least 350lb/ft at 7,000RPM which means it would also put out 466 horsepower. Historically, the smaller M3 motor has generally had a slightly higher redline than the M5 from the same period, so it's possible we will see a redline even higher than the F10's 7,200.
We won't know for sure until it's announced, but I'll be surprised if the M3 ends up with any less than 450 horsepower if it really does have ~400lb/ft of torque.