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I can pass this guy...
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8,167 Posts
which is what happens when you take a 25 mph turn going 50. Cathy, Terry's wife, who is sitting next to me in the backseat, grabs my leg. I grab the door handle. As we come out of the 270-degree turn, Cathy says, "I hope you have upholstery cleaner."
Umm, yea keep your 59mpg... I'd like to live not die. Turning off the engine and going around a 25mph turn at 50... Ok no power steering, no power brakes. Sounds like a wreck waiting to happen to me.
 

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Go-Cart Mozart
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3,177 Posts
I started slowing down in the truck, the 14.5mpg I was getting was starting to hurt too much. By cutting to the speed limit when in the truck and now using the bike to commute unless I have grocery shopping to do, I have cut my fuel bill by more than 100 bucks a month. I think this guy is a bit extreme, but I know I can use a break from the fuel costs.
 

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You got that right.
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10,228 Posts
Discussion Starter · #4 ·
I've experimented with it but not to the degree that the road-raging-hypermiler mentioned in that article. My Honda has a highway EPA rating of 35 mpg, and I'm consistently getting 40 mpg.
 

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Theres no I in threesome
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6,118 Posts
Fuck hypermilling, I can get decent mpg on my bike riding around like an asshole, so thats just what I'll do.

BTW, drafting behind tanker trucks is the best. The draft they leave is not turbulent and decently long, you can almost pull the clutch in and coast behind them forever.
 

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422 Posts
Fuck hypermilling, I can get decent mpg on my bike riding around like an asshole, so thats just what I'll do.

BTW, drafting behind tanker trucks is the best. The draft they leave is not turbulent and decently long, you can almost pull the clutch in and coast behind them forever.
Yup, Do the same in my cage.. Wish these kids tryin to race me, would understand how much saving gas means to me now-a-days..
 

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1,622 Posts
retarded, this guys shitty driving probably causes other people to use twice the gas he is saving and he is putting others in danger
 

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Banned
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I notice people out here driving way under the speed limits on I25 (which for the most part is 75mph)...they are very dangerous people to do 55mph in these zones. As prices go up, the slower and more of them there are on the roads.

I'm happy with my current milage. Maybe if they can not afford gas they should not be on the roads period heading out of town on the weekends, just a thought.
 

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Old school fool
1994 CB 1000
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5,725 Posts
retarded, this guys shitty driving probably causes other people to use twice the gas he is saving and he is putting others in danger
Fuck an A right. I hope he gets crushed by a Hummer. :twofinger
 

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Sexual Chocolate
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2,212 Posts

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The cake is a lie
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That guy must be the absolute most boring person in the world to have a conversation with.
 

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Theres no I in threesome
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6,118 Posts
Ummm theres a guy getting 100+mpg in his mustang on E85
E85 Mustang 100mpg
Thats impossible.

One gallon of e85 ethanol contains 76,000 btus. Convert this number into horsepower hours and you get about 30 horsepower hours. Lets say the guy is going 50 miles per hour, it would take him 2 hours of driving to get 100 miles, and this engine would be limited to using the equivalent of 15 horsepower average this entire distance, and this is NOT taking into account the thermodynamic efficiency of an internal combustion engine, or the rolling and aerodynamic efficiency of his POS mustang. With these taken into account, he would have to be running his car at 50 mph on the equivalent of 5 or so horsepower.

Gasoline is approximately 125,000 btus per gallon, converted into horsepower hours it is about 50. With a gasoline engine operating at an extremely high 40% thermodynamic efficiency, we get closer to 20 horsepower hours. A stock 5.0 mustang can get about 20mpg, so on this same 2 hour, 100 mile trip, it is more believable that the car uses about 100 horsepower hours (or 5 gallons of [email protected]% efficiency) giving the car an average power usage of 50 horsepower.

I don't believe for 1 second that you can get a 5.0 mustang to get 100mpg on anything other than snake oil.

To get 100mpg on any car, you would have to vastly improve the aerodynamics and the mechanical and rolling resistance before you should even think about improving the engine. This means hard skinny tires, a ridiculously slippery shape, a tiny frontal area, fewer moving parts, and less weight.
 

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Silent pipes take lives
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12,981 Posts
Thats impossible.

One gallon of e85 ethanol contains 76,000 btus. Convert this number into horsepower hours and you get about 30 horsepower hours. Lets say the guy is going 50 miles per hour, it would take him 2 hours of driving to get 100 miles, and this engine would be limited to using the equivalent of 15 horsepower average this entire distance, and this is NOT taking into account the thermodynamic efficiency of an internal combustion engine, or the rolling and aerodynamic efficiency of his POS mustang. With these taken into account, he would have to be running his car at 50 mph on the equivalent of 5 or so horsepower.

Gasoline is approximately 125,000 btus per gallon, converted into horsepower hours it is about 50. With a gasoline engine operating at an extremely high 40% thermodynamic efficiency, we get closer to 20 horsepower hours. A stock 5.0 mustang can get about 20mpg, so on this same 2 hour, 100 mile trip, it is more believable that the car uses about 100 horsepower hours (or 5 gallons of [email protected]% efficiency) giving the car an average power usage of 50 horsepower.

I don't believe for 1 second that you can get a 5.0 mustang to get 100mpg on anything other than snake oil.

To get 100mpg on any car, you would have to vastly improve the aerodynamics and the mechanical and rolling resistance before you should even think about improving the engine. This means hard skinny tires, a ridiculously slippery shape, a tiny frontal area, fewer moving parts, and less weight.
Sure enough.

Force of drag = 1/2p * v^2 * Cd * A / 29.91
p=fluid density (0.076 pounds per cubic foot is typical for air)
v=velocity relative to the fluid (MPH)
Cd=Coefficient of drag (~0.28 for a Corvette)
A=Frontal area (~21.3 sq. feet for a Corvette)
29.91=Constant to take common American measurement units into account (feet, pounds, MPH)

Even in a slippery Corvette, you suffer at 60 MPH from 27.277 pounds of aerodynamic drag.

Force [lbf] = 0.5 * 0.076 * 60^2 * 0.28 * 21.3 / 29.91
Force = 0.5 * 0.076 * 3600 * 0.28 * 21.3 / 29.91
Force = 27.277

Converted to HP at the engine, we'll assume a 1 foot radius at the rear tires, a 20% loss in the drivetrain, a 0.5:1 ratio in the transmission, and a 3.42:1 ratio in the rear end. The result? A requirement of 20 pounds of force at the crank. If the RPMs are at 1,500, that's a horsepower requirement of 5.7 HP.
 

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OO=[][]=OO
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7,410 Posts
50+ mph around a 25 mph clover leaf ramp is no big deal... i do it all the time in my cage, but it is usually with the pedal down and the back end hung out. lol... i must get 12 mpg doing them like that
 

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Theres no I in threesome
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6,118 Posts
Sure enough.

Force of drag = 1/2p * v^2 * Cd * A / 29.91
p=fluid density (0.076 pounds per cubic foot is typical for air)
v=velocity relative to the fluid (MPH)
Cd=Coefficient of drag (~0.28 for a Corvette)
A=Frontal area (~21.3 sq. feet for a Corvette)
29.91=Constant to take common American measurement units into account (feet, pounds, MPH)

Even in a slippery Corvette, you suffer at 60 MPH from 27.277 pounds of aerodynamic drag.

Force [lbf] = 0.5 * 0.076 * 60^2 * 0.28 * 21.3 / 29.91
Force = 0.5 * 0.076 * 3600 * 0.28 * 21.3 / 29.91
Force = 27.277

Converted to HP at the engine, we'll assume a 1 foot radius at the rear tires, a 20% loss in the drivetrain, a 0.5:1 ratio in the transmission, and a 3.42:1 ratio in the rear end. The result? A requirement of 20 pounds of force at the crank. If the RPMs are at 1,500, that's a horsepower requirement of 5.7 HP.
I got about 8.5 hp, is your math right?

v^3 * Cd * A = engine hp * 151,125

151,125 = (29.91 / .074225) * 375

This works out to bet about 8.5 horsepower worth of aerodynamic drag alone. When factoring in the rolling resistance of the tires on the ground, the brakes dragging on the rotors, the bearings and gears in the rear end, axles, and transmission, and finally the friction of the engine turning, the pistons going up and down in the bore, the power needed to change the pistons' direction several thousand times per minute, the valvetrain, the belts and accessories required to power the car, the water and oil pumps, and other various things, you're looking at quite a substantial horsepower load at 60mph.

That stuff can (and probably has) all been measured by engineers, but we can actually calculate that load based on the engine efficiency, its fuel flow in gallons per hour at 60mph, and the aerodynamic drag.

To make this easier, lets say the corvette gets 30mpg on the highway at 60mph. Fuel burn is then 2 gallons per hour at 60mph. Since there are 50 horsepower hours in a gallon of gasoline, that equates to 100 horsepower the car is using to remain at a steady 60mph. Subtract our 8.5 horsepower from the 100 and you'll see that 92.5% of the gasoline going into our motor is spent doing all the stuff above and otherwise being inefficiently exhausted out the radiator and exhaust as heat.

Internal combustion engines are extremely inefficient, but as of now there is no viable alternative.
 
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