The AC hurts, but not as much as they used to. It's much more about how you drive and what kind of driving you're doing. I just got back from a 540 mile trip over the Sierra to Carson City and back last Saturday. Top down the whole way, AC on all the way back. 320 miles on one tank, 11 gallons. So just BARELY less than 30 mpg. And I doubt I ever went below 70, and mostly never below 80. Well, except for that time I spotted the Nevada trouper on his Harley.

 

i get about 300 mi per fillup w/o ac...250 with.

 

In my civic manual, it tells me I will get less gas mileage if I turn on the a/c (worst). Even if I roll down the window I'll loose mileage. The best is to open the vents the manual says.

 

I am now getting upwards of 28-30mpg on two lane roads traveling about 60mph, but overall averageing only 45mph on 70 miles trips.

I am currently filling up with 5 gals. 93 octane and the rest (about 5 gals.) 87 octane. No detenation! seems to work fine.

Last year drove to Montreal F1 Race 350 miles @ 75 mph with A/C on and still averaged 28mpg!

 

I'll tell you why the gas mileage sux when the A/C is running. The A/C is so damned cold!!! It takes all that power to pump out the freezing cold A/C. I am actually quite impressed because I have been in other cars that doesn't start out cold at all and still get bad gas mileage.

Jeffrey.....feel that breeze...brrrr!

 

The car is a gas monster...

 

I believe this completely. A/C with car at constant speed shouldn't affect mpg too much. The car is more aerodynamic if the top is up as well. I got over 30mpg at about 65mph cruise control with top up and a/c on on trip to Page, AZ. Stop and go with a/c is another matter, I think.

 

I kept careful track of my gas mileage while driving all over the West last month and I can't detect more than about a 2 mpg difference in mileage when I had the air conditioner on. In all cases, I had the top down while the AC was in use.

Full mileage listing is at: http://www.geocities.com/srnelson_s2000/St...Statistics.html
_______________
S2000 at Balancing Rock in Arches National Park

http://www.geocities.com/srnelson_s2000/Day01.html

 

My wife and I just took a drive on Skyline Drive. Because of traffic (and Deer), I had the car in Cruise Control going up hill @ 40 mph (5th gear with AC on). It was amazing how much power the car had. I did occasionaly jump up to 60+ if I had room to pass a few loafers. I averaged 31.48 mpg on that stint. On the way home, we drove interstate @ 70-80 MPH in Cruise Control (6th gear with AC on). I averaged 31.19 that time. I think this is excellent considering the performance of this car. Very happy!!

 

ebertm--You were very precise in your gas mileage figures, even giving it to 2 decimal places. My question is were you precise enough to correct for odometer error. Most cars odos read high (mine by about 3%), thus overstating gas mileage, and it gets worse as the tires wear down. If we are going to be precise, let's be totally precise. Every S2000 is not going to have the same error and remember many have changed wheels and/or tire sizes as well.