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      03-27-2009, 04:19 PM   #45
bruce.augenstein@comcast.
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...I'll see if I can dig up Bruce Augstein's explanation, since it is arguable the best out there. Or maybe he'll just chime in.
Thanks for the plaudit. It's here.
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      03-29-2009, 09:11 AM   #46
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Hey JM1234, wouldn't the blue and red line meet where the 6MT hit 8,300 RPM (where the MT meets the CVT set point)?
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      03-29-2009, 10:02 AM   #47
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Hey JM1234, wouldn't the blue and red line meet where the 6MT hit 8,300 RPM (where the MT meets the CVT set point)?
Umm, well yes The 6MT plot was done using engine torque values from car dynos of a stock car (accounting for realistic powertrain losses). The CVT plots were done using published max torque/HP numbers for the engine (ignoring powertrain losses). I was trying to show how the values compared and that one was above the 6MT and the other below. Realistically, I doubt that the powertrain losses for a CVT would match those of a 6MT so the plots probably aren't supposed to touch where they do. Here's the plot you are looking for. I think your right, that doesn't simplify things. It still shows that an engine at max torque even with ideal gearing (CVT at 4000 rpm) will consistently put out less rwt than an engine with un-ideal gearing (6MT) shifted at max HP (actually shifted at redline). With the exception of the low speed torque that induces greater wheelspin but no more acceleration.
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      03-29-2009, 12:33 PM   #48
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Originally Posted by jm1234 View Post
Umm, well yes The 6MT plot was done using engine torque values from car dynos of a stock car (accounting for realistic powertrain losses). The CVT plots were done using published max torque/HP numbers for the engine (ignoring powertrain losses). I was trying to show how the values compared and that one was above the 6MT and the other below. Realistically, I doubt that the powertrain losses for a CVT would match those of a 6MT so the plots probably aren't supposed to touch where they do. Here's the plot you are looking for. I think your right, that doesn't simplify things. It still shows that an engine at max torque even with ideal gearing (CVT at 4000 rpm) will consistently put out less rwt than an engine with un-ideal gearing (6MT) shifted at max HP (actually shifted at redline). With the exception of the low speed torque that induces greater wheelspin but no more acceleration.
Great stuff. Fascinating that the RWT from an "inefficient" 6MT betters that of a CVT at the torque peak. That's a perfect way to show the value of gearing and RPMs.
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      03-29-2009, 11:41 PM   #49
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Good posts guys.
I have a head ache now
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      03-30-2009, 04:28 AM   #50
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Very informative posts, this forum is great, at times! Haha
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      03-30-2009, 05:15 AM   #51
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Very interesting...
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