hot weather hypermiling questions

[ikhoudvanu199]

Since this is my first summer with the insight, I've been trying to work out ways to hypermile without dying from heat exhaustion...so a couple of questions for all you experienced insighters

The Mythbusters(one of my fav shows) proved that it is more fuel efficient to drive with the windows down while driving around the city, and the a/c while on the highway...does this still hold true for our car?

Would it be more efficient to drive with the windows open 1/2 way or less...or drive with the a/c

I have adapted a technique on days when I can't live without a/c...I open the windows while off the highway, but while on the highway I only turn econ a/c on when I absolutly need it and when going downhill...and turn it to econ a/c off when going up hill, leaving the fan speed on high and recirculate on to try to keep it cool for as long as possible...is this the best way to keep cool and maximize MPG or is there a better way to use the a/c(such as keeping it on econ a/c on but turning the temp up, I keep it at 60 to get the most cool air out of as little distance running the a/c)

Also, I know that econ mode obviously utilizes auto stop...but while on the highway, does auto do the same thing as econ a/c on, or does econ somehow put less stress on the engine?

[HafNHaf]

you are doing it right! run as long as you can stand it without the a/c, and the windows open as little as possible. then roll 'em up and use the a/c only when the engine is under a light load. no hill climbing, no accelerating, etc. also, dont use the a/c when the engine is still warming up. the insight drops about 8-10 mpg with a/c on, when warmed up. when cold, the a/c will probably prevent you from getting into lean burn. thats about a 25 mpg hit.

[ikhoudvanu199]

sounds good to me, glad ive got the right ideas here

something im doing is right, cause my MPG keeps climing

[Guillermo]

Come on you hard core hypermileagers, use what the race car drivers do in extremely hot conditions to keep the mind sharp and the body comfortable:

http://www.coolshirt.net/racing-club-system12.html

[Willie Williford]

"the complete system weights 4lb??" According to my guestimation the number should be around 40 pounds.

Thats extra horsepower needed, easier to turn on the AC.

Willie

[Dougie]

I think when you have it in ECON mode, the A/C is less aggressive about keeping the temperature down. It runs the fan at a lower speed, for example.

Also, if you set the temperature knob higher, the A/C doesn't have to work as hard...

[ikhoudvanu199]

so who can tell me if its better to:

set the temp at 60, turn the fans all the way up, and alternate between a/c on and a/c off

or

set the temp higher(at say ~73) and leave it on a/c on mode

(this is all on the highway only)

[HafNHaf]

near as i can tell, turning the temp dial up just mixes in some hot air from the heater. thats the last thing i want! i run it set at 60 and toggle between econ a/c on and off, depending on engine load.

[red1dr]

Originally Posted by HafNHaf

near as i can tell, turning the temp dial up just mixes in some hot air from the heater. thats the last thing i want! i run it set at 60 and toggle between econ a/c on and off, depending on engine load.

Thanks, I was afraid it was set up like that.

With all the care Honda put into everything else, doesn't it seem odd that they wouldn't have a system that would toggle the compressor on and off to achieve the digital temp setting without wasting energy by blending in heated air? The HCHII has a variable compressor and runs on either engine or electrical power, so that would be even better but that system may not have been available when the Insight was designed.

[Dougie]

I just went on a long trip (Colorado Springs to Amarillo) with my wife, who insists on having the A/C on. It was really hot and sunny, and we left it at 70 in AUTO mode most of the time. (I cheated a bit when going up hills by pressing ECON twice, but you still get cold air for a minute or so.) We went the speed limit most of the time--not over Raton Pass!--and it was really windy, but we ended up with 69 MPG overall.

Ideally you would sit there and sweat with the windows up. On the highway at 70 MPH, you're probably into the operating region where the A/C is better than having the windows open. If the goal is to get the interior to some specific temperature, either AUTO or ECON will probably get you to the same point.