Quote:
Originally Posted by AeroMcAeroFace
In the Tahoe hybrid thread the car would only ever get 60mpg(US) due to rolling resistance, in the insight thread half of the drag was rolling resistance.
Theoretically rolling resistance is proportional to force applied, so a lighter car would have lower rolling resistance.
A car that generates significant lift has lower rolling resistance at higher speed.
Low drag shapes in ground effect often have high lift coefficients.
I am imagining a car, a bit like an ekranoplan, but never leaves the ground so the wheels always drive the car. Steering angle sensors, wheel slip sensors and brake pedal sensors cause the lift to stop and spoilers to create downforce pop up. Turning at speed can be assisted by aerodynamic aids.
As long as it is aerodynamically stable, in all directions, can dump lift as necessary I see no reason why this wouldn't reduce rolling resistance.
Obviously this is really complex but looking at cars like the huayra, certainly possible. Is it the case though that by the time significant rolling resistance reduction occurs, the speed is so high that rolling resistance is a tiny fraction of total drag?
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aerodynamic issues a small reduction will let me in the magic gear (EVT gear) which would significantly reduce powertrain losses
an
electrically variable transmission, which uses electric
motors to operate at
nearly any speed ratio through the
transmission.
which would eliminate powertrain loss.... which would at lest get me 35MPG IRL in my city(with a totally dead exhausted hybrid battery that is 13 years old) with the 6.0L v8...
the engine is barely idling at 1,050 rpm at 45mph,55mph . in the magic gear which would get me 35-40MPG on the highway.....
Honesty GM really limited it on purpose as they knew it could get more they did not have an Eco mode button which would have configured the TCM to use the EVT gear more often(or stay longer) at the expense of acceleration..which is a non issue due to the massive amount of Torque available ..
if I had new batteries it's possible to spin the wheels with the electrical motor
when it's not in the magic gear the rpm is a bit higher and will top out at 25-27mpg(IRL) at 59mph
the BEST ever was 32MPG with a slight tail wind (I just got lucky on that round trip..)
the normal LS2 6.0L engine.(it has a slightly different CAM and crank though). gets barely gets 9mpg in the city and 13MPG highway on the 4 speed auto (4L70E) (IRL) MPG which is all lost in the powertrain..
here is a cool photo
