Air conditioning making mileage worse? What a weird notion!!!

This is common sense. The AC makes the engine work harder, hence, burns more gas, HENCE, gets worse mileage.

Oh boy.

More Mileage Stats
 

FYI...more MPG stats. I've filled up twice so far....60%/40% hwy/city driving. Both tanks averaged about 19 MPG. I've got a Winning Blue 6MT. What would really make me happy is a fuel tank with about 5 more gallons in capacity....but I'm pretty darned happy with the car. I hope mileage improves with break-in as has been described on the forum and will be happily working on those miles.

I've been monitoring my gas mileage (premium gas only) closely due to all the discussions on the subject. With mix of highway and city driving, I'm getting almost 19mpg every time. I finally got a chance to drive mostly highway (70-75mph) and the gas mileage increased slightly to 21-23mpg. Kind of disappointing but pretty close to the EPA estimates. I'm hoping it gets better as RX-8 breaks in.

With the highway driving, AC was ON but I've found that AC doesn't hurt gas mileage noticeably on highway with my other vehicles. With my MX-6, I get over EPA on highway with AC ON or OFF. My guess is that AC only hurts in city driving, but RX-8 may be different. It's interesting that my Toyota Tacoma 4WD gets 20mpg under almost all conditions (highway or city). My MX-6 gets way over EPA estimates unless the temperature drops to freezing in which case my gas mileage drops significantly.

I'm wondering if switching to different tires will increase gas mileage (1-2mpg). Those OEM tires give nice traction, but are very soft and may be bad for gas mileage (i.e. high rolling resistance).

I have had my RX-8 for 3 weeks now. The gas mileage is horrible. I don't drive much, I am retired, and I seem to visit the pump too often . The necessity for 91 octane gas at the current price (in California) is a real killer. The buy back plan works for me. Thanks for your input. 2,004 Mazda RX-8,
6 speed, Touring PKG.

i'm right at about 1900 miles now and the last tank i just had got me 20.8 mpg, the best i've seen out of my car so far. 6mt/touring...though still strongly considering the buy back too.