Quote:
Originally Posted by mcrews
the key to the vette is certainly the tranny. i believe the last two gears or overdrive gears
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The numerical ratio doesn't really mean much since you have a final drive ratio at the axle to worry about too, but yes, the tranny has a very large gap in gear ratios going from 4th to 5th to 6th (I think it is like, 1, 0.71, 0.5? ZR1s are 1, 0.8 0.67 or something), whereas say the Honda s2000 has a completely useless 6th gear which is barely longer than the 5th gear. Combined with a somewhat long final drive, you get your ridiculously low highway rpm. A fuel efficiency conscious driver could use that 5th gear to handle low speed cruising duties since the 6th gear probably doesn't go far below 40mph (not sure what the actual rpms look like though).
Of course the motor is so big that in the end it's still less efficient than a smaller engine, but considering how it has ~3 times the displacement of these 4 cylinder engines, not a bad result at all.
One problem with manual transmission specs is that since they don't shift themselves, manufacturers have emissions (enrichment) to worry about when the EPA test decides to floor the gas on the highway in top gear (which apparently does happen), and drivers are too lazy to shift and will complain about lack of power... :/ The Corvette having so much power doesn't encounter this issue as much as smaller engines, which could be insanely fuel efficient with more fuel efficiency minded gearing, if only people didn't require 6th gear to have passing power.