Thread: RJ's STi
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Old 10-07-2015, 02:17 PM
Bram Bram is offline
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Quote:
Originally Posted by nauli View Post
Spot on Shane...the relationship isn't a straight line....and obviously will depend on type (hub or rolling) and brand of dyno. However straight line extrapolatioin will give a rough idea of ATW to flywheel. As a rough guide, I seem to remember that a 206 kw STi made around 145 -149 ATW...
Drivetrain loss is not directly related to total power. But it is related to the rate at which you accelerate the drivetrain.

The components in the drivetrain have mass, and inorder to get them spinning it requires energy. The faster you accelerate them, the more energy it saps. Plus ontop of that you also have frictional loss aswell. That is what makes up drivetrain loss's.

On the road, the rate of acceleration, and therefore drivetrain loss is locked into the vehicle road speed. On a dyno, you can change the way the dyno loads the car, and therefore control the way the drivetrain accelerates.
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