After driving around the past 600 miles seeing no better than 16-18 MPG, I was interested to see how my car would fare on the highway. Through some very conservative shifting and a 75MPH cruise speed, I managed to eek out 23.8 MPG.

Really, this came as something of a relief. I saw 14MPG on my first tankful and wasn't too optimistic for mileage on the long haul. It seems like temperance with the right foot is the key to fuel economy with this car.

Maybe, with a fresh coat of wax and a little extra tire pressue, I could even see 25 MPG. Of course, that's not nearly as fun as dropping the hammer and watching things spin. haha

No, I don't have a clue what version my ECU is running. The car itself was manufactured in Feb 2004.

 

How many miles was your trip?
I've never seen mine above 19 MPG even with conservative shifting, but to be honest I don't give a darn about MPG knowing that I bought a kickass sports car.

Also what are you basing your milage numbers off?

 

It was a 140 mile trip, almost exclusively turnpike miles.

I agree on the kickass sports car part. haha

 

Sounds just about right. I just got 22.3 on a 600+ mile trip mostly @ 70-80 mph w/80% hiway. I assume you have a 6 spd too.

Glad you bothered to post. If all of us that get decent mileage bothered to say so, balance would be shown here about the true nature of the 8 IMO.

 

i had my 8 for 10 days and took a 700 mile trip all Highway and got 24 miles to the gallon . i do have a automatic. Its a pain to cruise the beachs here in a MT.

 

22-23 still isn't impressive for highway. The Viper supposedly gets 20 on the highway...

 

Is that your MV Agusta parked next to your RX-8?

 

That is surprising that you even get that high, because on average when I go back and forth to school on the highway ~60 miles, I get 17.14 MPG on average that is the best I ever got a few weeks ago. My tank totals out to not more then 230 miles to reserve. I use Sunoco 94 octane, what do you use buzzwordenabled?

 

I've been using 93 Octane from BP/Amoco and Wawa.

 

Yes it is. With competition header and SilMotos, it barely gets 30MPG. haha. A small price to pay for 127HP at the rear wheel.

http://buzzwordenabled.com/mv

 

i hit the 25mpg mark yesterday on a trip

 

i couldnt break 15 mpg if i drove highway the entire time. with the windows up, the a/c off, granny shifting, cruising @ 60 on a downhill.... i mean seriously, this sucks! I sit here in absolute awe and disbelief when i see some people posting 20+ mpg. and getting over 300 miles out of a tank of gas, Im lucky to break 200 miles on a tank. I have 3600 miles on the car. and have owned it since birth. gas has had absolutely no improvement from day one to now. Mazda says 18/24 mpg. we get 13/15 mpg. I pay friggin $28-$30 ever 3 days. thats $250-$300 a month. screw that. I WANT A SOLUTION. I WANT A FIX. I WANT AN EXPLANATION. FROM MAZDA. IF EVERYONE CALLS / E MAILS MAZDA... THE PEOPLE WHO ARE EXPERIENCING THE SAME ISSUE AS I AM. OUR VOICE WILL BE HEARD. AND MAZDA WILL BE FULLY AWARE THAT THE PROBLEM IS WIDESPREAD. AND A FIX COULD BE AROUND THE CORNER.. OR ATLEAST SOME FORM OF REISBURSEMENT.. WHO KNOWS..www.mazda.com... e mail them. I DID!

 

My A/T gets 21.4 MPG with 80% highway.

Date Start End Miles Gallons MPG Type
5/5/04 23 271 248 12.46 19.90 Premium
5/11/04 271 548 277 13.03 21.26 Regular
5/17/04 548 828 280 12.48 22.44 Regular
5/24/04 828 1091 263 12.53 20.99 Regular
5/29/04 1091 1375 284 12.66 22.43 Regular

I wish it were better.

 

No its not. try paying 3 x that amount and then its expensive.

How much fuel the 8 uses is directly linked to how you drive it.

Drive it slow, keep the rpm below 3-4k and it'll give you 25%+ more mpg. Problem with the 8 is its so easy to drive uneconomicaly.

 

I only pop in here every once in a while so I'm a tad ignorant on RX-8s, but it sounds like there's something wrong with your car if you're getting that kind of millage, or you drive it like a nut. My old TII gets better millage than you're getting, but it's quiet easy to to drop it down. The worst highway millage I've ever gotten was about 15mpg, but that's driving it VERY hard. Best on the highway I've gotten was about 23mpg.

 

I just returned from a 1386 mile trip out to Colorado for the Rocky Mountain RX-8 Club meet. This was primarily interstate highway with 2 very aggressive drives through the mountains.

I used a total of 60.5 gallons of premium unleaded ($131 total)which equals 22.91 mpg total for the trip. Not too bad IMO

My best run was coming back from Colorado -- I went 322 miles on 12.5 gallons which is 25.76 mpg :D This was done with all the windows up, AC on, sunroof closed and in 6th gear the whole way -- no stops. Also went from about 4000 ft altitude to 1000 ft altitude (in other words -- down hill the whole way). Speeds ranged from a low of 75 to a high of 110 with a usual cruising speed of 88 mph.

 

This is a previous thread on high MPG highway miles:

RX-8 Discussion > Mileage: Long Distance Cruising: 27.7 MPG@60 mph; 26+ MPG@65; 25+ MPG@70; 24+ MPG@75
https://www.rx8club.com/showthread.p...threadid=25283

This is a previous thread that summarizes results from rx8club owners:

https://www.rx8club.com/showthread.p...threadid=13404
RX-8 Discussion > RESULTS: Statistical Analysis of MPG -- Long

 

A few thousand miles ago I wrote in a post that the RX-8 could not get 24 MPG going over a cliff. A couple weeks ago I drove back to VA from southwest PA (admittedly, initially downhill) and got 25 MPG. My commuting mileage now seems in the 16's instead of the 14's and is still improving. What gives? I'm now over 7K miles on the car; I have the M Flash and the CZ cat - midpipe resonator / Borla along with the CZ computer. And, though I still "wring it out," I try to cruise under 3750 RPM where I can (unless, of course, the situation or 6th gear demand more revs). But I've tried that in the past. Basically, who the heck knows? But as you put some miles on the engine, there's hope!

 

I've been getting 18 pretty consistently around town. Bought it 11/04, have 10K+ miles on it already! I think I have the L flash based on the date I got it. I've seen better than 20 on roadtrips, as high as 25 once when I babied it downhill. The 8.5K RPM beep is a pretty common occurrence for me - it's too much fun not to!

I guess my point is that I'm getting acceptable mileage given my propensity for a lead foot!

 

buzzwordenabled "off the grid" hunh?! you just located yourself! i can find my way around back there just by which WAWA is closest to my destination