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This power output and torque curve looks a lot better than the one in the brochure, which is just straight lines on a graph..

 

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Thanks for the power curves on the M5.

Anyone have such curves for the 540i. My 540ia doesn't have any life until 3000 rpm. I wonder whether car acceleration lags at low engine speed because of the torque converter or because of the shape of the torque curve. If the 540i curve is fairly flat like the M5's, then I suspect the 5-speed 540i would be a significant improvement.

Richard
 

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I'm actually quite curious why there is a little blip on the torque curve at about 3000rpm. Just being a little curious on what the engine is doing there to have that kind of effect.
Thanks
Terence
 

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Look nice, but hard to know how they got it. Could have been a "loose" interpretation by an artist?

John Hennessey dyno'd a stock M5 a while back as a benchmark against which he will measure the performance of his aftermarket parts. The dyno graph is still on line at his site. THAT graph I trust. Incidentally, his HP numbers came out a bit higher than this graph shows, if memory serves.

Sorry, don't have the URL handy but I'm sure someone here does...

(John used to watch this board but has been very quiet lately. Still lurking out there John?)
 

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Found the info on the Hennessey site:
http://www.hennesseymotorsports.com/

(On the site, drill down to the M5 page, then click "introduction")

Note that at the time he did not disable the DSC which would not let him test above 5600 RPM - still these numbers suggest the Japanese graph is not accurate.

The following is a direct quote from the site. You can go there to see the graph.

"Peak Rear Wheel HP: 317 RW HP @ 5600 rpm (almost 1000 rpm below the factory advertised peak power of 6600 rpm)"

"Peak Rear Wheel Torque: 320 RW LB-FT @ 3000 rpm with over 300 RW LB-FT available from 1800 to 5200 rpm - an incredibly wide and powerful power-band."

"Since the M5's computer prematurely limits max rpm at 5600 on the dyno, we can interpolate the data measured and estimate that the motor produces close to 345 rear wheel hp at 6600 rpm. This equates to what a 400 flywheel hp motor should produce at the rear wheels."

/Greg
 

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I found it on the BMW Japan website...
 
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