Quote:
Originally Posted by theDreamer
His 1.2% is the difference between a MT and an AT, not from your flywheel HP numbers.
For a AT 7 speed I am unsure of 1:1.
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Exactly -- and those < 250 numbers must have been from a Mustang Dyno.
On the Website that Shall not be Named, it was a difference of 5 whp and 2 lbft of wtq between the MT and AT. That's pretty inconsequential
5th gear is 1:1, but I've been told to dyno in 4th... in 3rd gear there is some sort of a limiter, so not a good idea to dyno in 3rd.
EDIT: Yep.
On a superflow dyno (they dyno very low!)*
6MT = 261 whp and 212 lb/ft wtq
7AT = 256 whp 210 lb/ft wtq
Assuming 332 bhp
6MT drivetrain loss = ~21.5%
7AT drivetrain loss = ~22.75%
That's pretty awesome, especially considering the 7AT generally performs a little better in track tests of straight line acceleration.
I believe dynojet numbers on here for both transmissions will corroborate with that, although both will be in the 270's for whp.
EDIT: Going by
dynojet numbers, I'd say drivetrain losses are between 16.5% and 17.5%, with no clear evidence of a difference between the 7AT and 6MT.
For sake of argument, assume the estimated 1%-2% difference at the most is probably about right, but curiously I only see any evidence of that difference in the midrange rather than at peak.
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*Regarding which kinds of dynamometers skew
realtively high or low, see further here:
http://www.newcelica.org/forums/show...56&postcount=1
and here:
http://www.turbomagazine.com/tech/03...ash/index.html