Glyphon

actually, no. the epa does their tests at 60mph. so, the estimated 24mpg is at 60mph, not 65. in a large portion of circumstances, 65mph will yield lower fuel economy than 60mph due to the increased wind resistance.

dwynne

Huh? The EPA test calls for a MAX of 60 with an average of around 48mph. While I agree that going 65mph has increased wind resistrance than going 60, it does not matter for an EPA discussion since the car is strapped to a chassis dyno type rig for EPA tests - so there is no "wind". In an EPA test the differences between going a max of 60 or 70 or 80 would be slight, due no actual wind resistance. Just one of the many flaws in the system.

Dennis

dwynne

Not really true, while CR found that 90% of what they tested did not match EPA numbers, they amounts they were off varied widely. Hybrids do really well on the EPA test - they have an "economy" light that the test drive must obey and use 0 gas during the "stops". The drop off from EPA to real world is staggering on those cars, and several others - examples are listed in the CR story which is available online for free now. So while 90% could not match EPA the amounts could be a little or a LOT - and then 10% got EPA or even better. If you compared a car that returns better real world numbers with a similar car with the same EPA number that got a lot worse, you could tell NOTHING about real world economy - even though they both have the same EPA number.

My S gets EPA or better, the 8 gets a lot worse. So looking at the two numbers does not give you a solid answer on how much better/worse one is than the other. You can't say the "8 used only 20% more gas" or anything. You can GUESS that real-world the 8 will be worse - and you would be right. But if you compare the S VS Element (for example) the S gets better than real-world than the Element even though they have similar EPA numbers.

Dennis

Glyphon

ok, so my referencing the EPA was slightly off basis, but the in-regards to the person that i was responding to, it does make sense.

dwynne

Correct. On the EPA test you could strap a "barn door" or UPS truck or something and get the same EPA number as you would putting the same drive train in a low-slung aero-coupe.

In the real world, going slower = better ecomony everything else being the same.

Dennis

MTCD01

You missed the point. My car gets 22 MPG at 90 MPH on highway trips with the AC on. Someone stated that for every 5 MPH you go over 65 MPH you lose 1 MPG. I was being sarcastic in reply by stating that if true my car (keep in mind it's been averaging 12.5 MPG city for nearly two years) would get near 30 MPG on the highway at 65 MPH with the AC off. If tru this would best the EPA number by 3-6 MPG.

JeRKy 8 Owner

I wonder when people are going to start creating topics about things we didn't know about two years ago...

Glyphon

i believe zoom44 has gotten ~27mpg on highway trips. and if you are getting 22mpg at 90, then chances are you would be around 26 or 27 mpg if you slowed down.

RX8Sick

not when you are cruising. I get better gas mileage using the cruise control at higher speeds.

Glyphon

yes, even when using cruise control. wind resistance is wind resistance. you get better fuel economy when using cruise control because the computer is delivering just enough gas to maintain that speed more accurately where as if you are manually controlling the speed there is a greater range around the target speed.

you'll speed up a little and go slightly faster (using more gas), then you'll slow down to a little below the target speed, requiring more throttle to get back up to the target speed (which uses more gas).

all things being equal, cruise control at 70 will always get better gas mileage than at 80.

Roaddemon

I believe only the prototype and very early renesis were hand built. They are all mass production assembly line made after that.