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Hello guys,

I rescently bought a brand new BMW x4 m40i and being loving it since the first moment I took it out of the dealer
I am currently a little bit below 500km (around 310 miles) and have floored it a couple of times (full throttle) but I noticed on the sport display that the car is delivering less hp than it is supposed to... I called my dealer and he told me that the engine "may" reach the full power once the odometer passed the 2000 km break in period (1240 miles) but I do not know if I can believe that.
Can you please tell me what do you think or if you have experienced something similar?

thanks guys
 

· Nuclear engineer
02/2012 X5 35d M57Y CPO 125+K miles NOKIAN WR G4
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Something similar; the Basic Computer indications use obscure algorithms that never match hand calculations.

Would it be better for you for the computer ‘sport display’ to be stuck on nameplate power?

Felix Navidad. Comparte el beso de la paz.
 

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It would be worth it to get a log monitor. I use MHD. And I can say when my HP is lower sometimes it is related to my turbo boost PSI. Other times it just hits a weird spot in the RPM and gear. Using MHD stage 2 if I have 340+ hp OR 490 lbs torque then it running smooth.
 

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It's helpful to know the definitions of power and torque.

Torque is the amount of twist the engine delivers to the input shaft of the transmission. Torque is force x moment arm (e.g. lb-ft, or N-m). Turbocharged BMW's produce their maximum torque over most of the RPM range, from about 1500 RPM up to about 1000 RPM below the redline. The maximum torque of turbocharged BMW engines is governed, creating that "flat line" of maximum torque on a graph.

Energy, or "work," had many definitions. For mechanical "work," it's force x distance, which is also the units for torque. If you lift a 20 pound bucket of cat litter from the floor to a shelf five feet off the floor, you have transferred 100 lb-ft of energy from your body to the bucket of cat litter. If the bucket of cat litter falls off the shelf, it will accelerate due to gravity before hitting your toe. That 100 lb-ft of energy will be converted to kinetic energy (1/2 MV^2) before it hits your toe.

Power is the rate of energy being produced or transferred, or "energy/time" or force x distance / time. If you are pushing your broken down BMW with a force of 50 pounds and the car is moving at 1 MPH, you are transferring 50 pounds miles/hour of energy from your body to the car. "Pounds x miles / hour" is a valid but unusual unit of power. The common units of power are horsepower and Watts. One horsepower is 550 pound-feet / second. A Watt is a Newton-meter/second.

Torque can be visualized as a point force acting tangentially on the outer edge of a flywheel. A good example would be a flywheel with a handle near the edge. If you have a one-foot diameter flywheel, the radius would be 0.5 feet. If the flywheel is turning at one revolution per second, that hypothetical point of the force acting on the flywheel is moving at 0.5 feet x 2 x Pi per second. If that hypothetical force is two pounds, the power imparted onto the flywheel is force x velocity or 2 pounds x 0.5 feet x 2 x Pi / per second, or 6.28 pound-feet/second.

The point I'm trying to get to is that you can see the maximum torque your engine produces at any RPM between about 1500 and 1000 below redline. But, to see the maximum power, you have to have maximum torque and also have the engine running near its redline.

Here are data sheets of the 228i, M235i, and M2 from Road & Track magazine. Notice the maximum torque lines (blue) are flat, but the horsepower lines (red) increase with RPM and only reach their maximum values near the redlines. So, you can easily "peg" your torque meter on the Sport Display by keeping the "pedal to the metal (carpet)." But, to "peg" your power meter, you need to have the pedal to the carpet, plus have the engine running somewhere around 6000 RPM.


Car Font Wheel Material property Parallel
 
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