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Old 12-08-2008, 09:39 AM #2199  
chrisn chrisn is offline
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Quote:
Originally Posted by heavychevy View Post

Originally Posted by chrisn
Be careful with those formulas. Hard to argue with the basic concept that trap speed DEPENDS on power and mass (Newton taught us that).

Issue is that the formulas you are using include some baseline/calibration constants and coefficients that make the formula work accurately only for a certain class of cars/conditions.

HC's response:

WRONG, AWD decreases trap speeds as does a better launch. Notice that Johns fastest ET is not his highest trap speed. This is very common. RWD and AWD cars of the same kind will always net higher trap speed in the WRD car due to less weight from the additional components and less non-aero drag.

This is drag racing where powershifts, sometime clutchless are common, no different raping a manual than a GT-R tranny that is planning on breaking anyways if you launch it.
HC: You make my point for me. These formulas have an arbitrary baseline. They don't "know" about the any of the factors you highlight and therefore cannot be relied upon for precise insight into crank HP when comparing different cars with different drivetrains. My point is strengthened by the fact that the OP on this OT sub-topic himself included results from a few different magic formulas, and the results varied quite a bit.
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