ask tim questions/ advice thread.
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forced to marry and stay with a fat obese nasty prostitute or give the prez a bj on live tv?
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if you havent been in a small plane its worst, cause your eyes and brain say we are moving and your body says oh no we are not. eyes and brain go asshole we are moving, cant you see? body says fuck you we are not moving at all. so they fight and fight and eventualy your body says, you know what fuck you brain, see if you can stop this!! then you throw up.
if you havent been in a small plane its worst, cause your eyes and brain say we are moving and your body says oh no we are not. eyes and brain go asshole we are moving, cant you see? body says fuck you we are not moving at all. so they fight and fight and eventualy your body says, you know what fuck you brain, see if you can stop this!! then you throw up.
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kings cannot fall.
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kings cannot fall.
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Just consider the resistances. Rolling resistance is constant; aero resistance goes up by the square with speed. Aero will usually dominate around 45-60mph. But, like you're alluding to, BSFC improves with rshared_pm up to a certain point. After some hand waving and magic, you'll wind up with about the (interstate) speed limit for the average vehicle.
I do a lot of distance driving and can attest to this. Driving a box like my Element, you get significant economy differences between 75mph and 85mph. At 85, it's just about as bad as in-town. The Altima has the same trend at those speeds, but it's less pronounced.
I do a lot of distance driving and can attest to this. Driving a box like my Element, you get significant economy differences between 75mph and 85mph. At 85, it's just about as bad as in-town. The Altima has the same trend at those speeds, but it's less pronounced.
Mpg For Speed - Fuel Efficiency Vs. Speed
Basically, a gasoline engine is most efficient just shy of full throttle, at whatever RPM. As you reduce throttle, pumping losses from the partially closed throttle plate, among other things, reduce efficiency. Approaching full throttle, most ECUs go a bit rich to stay safe. As an aside, those pumping losses are part of why diesels are more efficient... no throttle plate.
So ideally, you want to cruise just shy of full throttle....
Except that like Epstein said, aero drag increases with square of speed. You see that in the chart above, as MPG decreases parabolically as aero drag becomes dominant.
Really, you want a car with an engine that requires ~80% throttle to cruise at 65mph, and to cruise at 65mph. This is why old school econoboxes like early 90s civics can crank out 35+mpg - they're sized with engines that are very much in their efficient range at cruise.
You look at something with a real big V8, it'll be at 10% of max power in highway cruise.... which puts it in a real inefficient range of the BSFC map.
Anyway, that's how hybrids get such good mileage - size a smaller engine, use the electric motor to keep fat americans happy with acceleration. You'd get the same highway mpg, better even, if you ripped out the hybrid crap - you'd save on weight, which would minimally improve highway mpg, at the cost of off the line acceleration and some regen braking around town.
Here's a bit more, if anyone cares:
https://www.tamparacing.com/forums/n...ml#post7380469
im jk.... but seriously
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kings cannot fall.
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i could seriously drink that shit.
charlie and millies is prety good too, just weird.
i call it ketchup and crackers pizza, but i still like it.
and waldo, hes probably at carabas, or at home. but probably not working on his car.
charlie and millies is prety good too, just weird.
i call it ketchup and crackers pizza, but i still like it.
and waldo, hes probably at carabas, or at home. but probably not working on his car.
