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      12-13-2010, 09:02 AM   #44
Pete_vB
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Drives: '69 GT3, GT4, 1M, 912
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Location: SF Bay Area, Shenzhen, Oman

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Quote:
Originally Posted by Madozu View Post
Just played around with my (quite old) version of CarTest 2000. As Swamp showed, the 50Nm overboost doesn't make a huge difference ... but setting max. torque at 1500 rpm or 4500 rpm makes quite a bit of a difference. I was using identical data of a 1M with one exception:
  • BMW 1M (LOW) has max. torque at 1500 rpm
  • BMW 1M (HIGH) has max. torque at 4500 rpm
Good example of why the shape of the dyno curve is critical, as area under the HP curve, not peak hp to weight, is critical.

There are a number of dynos floating around to model from, such as these for the 320 hp 35is. Obviously the 1M is going to breath better up top than this, so I may have been conservative killing power about 6000 as fast as I did in my estimated dyno.
http://www.bmwblog.com/2010/09/12/dy...vs-n55-engine/
BTW, I think your weight number above is off.
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