What 0-60 acceleration would you accept for good fuel economy?

[Will]

Originally Posted by SuperTrooper

My point is: Do you think that a car that takes 20 seconds to reach 60 mph could have accelerated out of that situation?

I don't.

I know there is no way my Metro could have done it. I would have had to punch the clutch, the brake and maybe even popped the E brake just for good measure.

I know that the 1996 Camaro Police Service Package I had would mop the street with just about anything including the riced out compacts, but in the end it really did not matter worth a crap. Speed is an illusion in the fact that there is ALWAYS someone faster. Even when I put a 100 shot in that car there were still races I did not win. Yes, it was on the track.

Your best bet is to drive smarter rather than faster. Please understand I say this in a caring manner. You had no idea how fast he was going to come over, and there is the possibility you may not have made it. If you did not have that power at your command you would have hit the brakes. Your fancy motoring did not help you, buddy, it almost got you killed.

Please don't be offended, just think about it for a little bit.

[Will]

Back on the subject... I vote for the 20 seconds or more. I am trying to do something here, and that is save $$$$. That means that I can provide for my family just a little bit better, and help to save the planet at the same time. It's a win-win.

I do not give a rat's ass about what the people behind me think about how I drive. I KNOW that what I am doing is the right thing, and they are wrong in their SUVs that never see the end of the pavement rushing from one place to another.

[lyd]

I don't care how long it takes me to get to 60 mph. I'd like to be able to maintain 60 mph, or even 55, without using more pedal than seems optimal for FE, and the Geo can't to do that.

I don't think I'd trade this car for anything, though. I really love it. When it dies someday there is at least a 50% chance I'll get another one just like it. (The other side of the coin-flip is for a small diesel.)

[SuperTrooper]

Originally Posted by Will

I know there is no way my Metro could have done it. I would have had to punch the clutch, the brake and maybe even popped the E brake just for good measure.

I know that the 1996 Camaro Police Service Package I had would mop the street with just about anything including the riced out compacts, but in the end it really did not matter worth a crap. Speed is an illusion in the fact that there is ALWAYS someone faster. Even when I put a 100 shot in that car there were still races I did not win. Yes, it was on the track.

Your best bet is to drive smarter rather than faster. Please understand I say this in a caring manner. You had no idea how fast he was going to come over, and there is the possibility you may not have made it. If you did not have that power at your command you would have hit the brakes. Your fancy motoring did not help you, buddy, it almost got you killed.

Please don't be offended, just think about it for a little bit.

If I'd hit the brakes I'd have been smooshed up against the guardrail by either the side of his trailer or the rear wheels. My only option was FORWARD, my car responded, and I made it. I choose not to give up the forward option in the future. You've made a different choice, that's all.

[SuperTrooper]

Originally Posted by jamesqf

Something to think about: the fuel economy vs acceleration thing seems to be an artifact of internal combustion technology: that is, there's no physical law that says that the energy needed to reach speed X depends on the rate of acceleration. (Just the opposite, in fact.) So if you had an electric car, or a hybrid with good boost, it seems that you would no longer be affected by that tradeoff. Do 0-60 in 5 seconds, or 50, the energy used would be the same.

If this were true then driving style would have no impact on battery range. I bet your EV powered buddies here would disagree with that. For a given mass greater acceleration requires more energy.

[MetroMPG]

Did you know CoyoteX has a diesel freight train horn in his Metro? Wonder if that would have corrected the trucker's "drift"...

[jamesqf]

Originally Posted by SuperTrooper

If this were true then driving style would have no impact on battery range. I bet your EV powered buddies here would disagree with that.

So does it? I don't know, since I haven't driven an EV enough to say from experience. But if so, I'd like to know why.

For a given mass greater acceleration requires more energy.

False. E = 1/2MV^2 is basic physics: Kinetic energy - Wikipedia, the free encyclopedia The amount of energy required to reach a given velocity is the same, regardless of how long it takes. The fuel economy hit in cars must be due to different engine efficiency at different load/throttle.

[MetroMPG]

Originally Posted by jamesqf

So does it? I don't know, since I haven't driven an EV enough to say from experience. But if so, I'd like to know why.

It's true.

1) Electrical resistance increases with current. So all else being equal, accelerating rapidly is less efficient than turtlefooting it. Ohm's law - Wikipedia, the free encyclopedia

2) Also, the faster you draw energy from a lead acid battery (don't know about other chemistries), the less total energy (capacity) you get from it. Peukert's law - Wikipedia, the free encyclopedia

So to maximize efficiency (range) in an EV, accelerate gently, keep top speed down, drive with load, and coast to stops.

[jamesqf]

I think you misunderstand Ohm's law. The resistance of a conductor doesn't change with current (neglecting effects of temperature changes, and that's avoided by selecting an appropriate motor so the current doesn't cause appreciable heating). Resistance converts a fixed percentage of the energy in the current to heat.

As for losses in lead-acid batteries, that's another artifact of the technology. If your electric car stores its energy in capacitors, high speed flywheels, or even batteries with a different chemistry, you aren't going to see those losses. Build an electric car with the right technology, and you can have good acceleration with no loss in energy efficiency.

[Formula413]

Originally Posted by Will

the 1996 Camaro Police Service Package I had

You had a B4C? Sweet! What did it run with the 100 shot? I will venture a guess of 13.1, am I close?

Originally Posted by Will

I do not give a rat's ass about what the people behind me think about how I drive. I KNOW that what I am doing is the right thing, and they are wrong in their SUVs that never see the end of the pavement rushing from one place to another.