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widebody911 widebody911 is offline
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While I am not a dyno expert (and I don't play one on TV), I look at it this way: the RWHP numbers are lower than the flywheel numbers because of losses thru the transmission; by the same token, the RW torque numbers are *higher* than the flywheel numbers, because of the mechanical advantage of the transmission.

If I use a 5' cheater bar to break the axle nuts loose on my VW, I'm exerting (let's say) 350 ft/lbs of force (ie RWft/lb), but that isn't the same as eing able to bench 350 (FWft/lb).

So, if the common drivetrain loss factor is given as 15% (I've seen up to 20% quoted) to convert RWHP to FWHP, then likewise, you'd need to apply a similar *gain* factor to torque.

Example (for illustration only!) assuming 15% each way:

RWHP * 1.15 = FWHP
236 * 1.15 = 271.4

RWft/lb * .85 = FWft/lb
412 * .84 = 350

Those numbers are somewhat in line with the table for the RS at http://www.paulweir.com/rebuild/911engine.html
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Last edited by widebody911; 02-22-2002 at 11:59 AM..
Old 02-22-2002, 11:52 AM
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