Did I just get under 13 MPG on my 1st tank of gas
 

Well,

1st tank of gas is under my belt. I drove about 178 miles and filled the tank: 13.92 gallons.

My driving was 75% suburban about town; balance was hwy and a bit of Manhattan. Never went higher than 4.5 to 5K and didn't push “too” hard when accelerating. The car is a joy and has respectable low end IMHO. I am not one to do jack rabbit starts but do like to get off the mark quickly nonetheless.

Here is one area I hope to see improve over time.

As the engine breaks in I expect to see better numbers, however I wonder if the engine will give me better mileage if I rev the gears higher before shifting up or continue to shift around the 5 to 6K mark?

Any thoughts? My VIN# ends in 19173 and I thought for sure I would start off with better numbers.

In all other ways, I am super impressed with this car.

Claude H.

Obvious question is how full was the tank when you got it?

Did you fill it or the dealer? I'd wait for a couple tankfulls you have done. And record your perceived driving style for each tank.

In just normal driving, I've found high-rpm use, that is staying in a lower gear than necessary, to suck most gas. E.G., its lots of fun to drive around 50-60mph in 3rd or 4th, but you'll really suck gas then.

IOW, shift up always, unless you have a definite reason not to. 5th works great around town, even 6th is amazingly flexible at somewhat higher average speeds

I am at 12.5 mpg and I have 500 miles on my car......i am hoping for improvement....if not Mazda will hear about it. I drive mostly around town in a suburban area and drive about average......not super fast, not slow. I have an automatic. I'd be interested to here if your's improves.

My first few tanks really got poor mileage. I attributed it to 2 things:

1. unbroken in engine tightness & other mechanical mysteries
2. my unfamiliar nature with the car and the optimal shift points

It should get better. When I refill my tank, it takes just less than 12 gallons, and I usually have 230 miles on the clock.

With all the focus on the forum over gas mileage, I paid very close attention to my results the first 5 or so tanks.

The results were

Highway = 20 mpg
City = 16 mpg

I quit looking at it after that. I think it is a non-issue. If you want 30 mpg by a civic.

I think that's a bit harsh -- most people aren't expecting "30mpg". They simply want the hard numbers to come close to what was advertised. Can't blame them for that.

I'd say my fuel consumption is quite high, I find myself in third quite often round town - it's more fun :)

I don't use the car as a long distance commuter - I wouldn't have got it for that purpose. I got it to enjoy.

My first two tanks have been 16.5 and 16.25. This is about the same as what my truck got so I'm pretty indifferent. If it increases over time that would be cool, but if not... eh, whatever.

-JiM

i enjoy driving the car too much to even think twice about how much i spend on gas. right now i dont give a $hoot, but if u guys are curious im probably filling it up every 3 days. for right now it's well worth it and i love this car. i have no regrets and no problems, and if i can go back in time ill buy this car again and again and again. booya

Short trips eat up gas in the 8, if I just go back and forth to work 8.5 miles, I use a lot, when I go on longer trips like say 50 miles, hwy only I get more economical mileage. And yes I notice if you shift more, (in the manual it says you can cruise at 42 or so in 6th) not as much torque, but that's what downshifts are for. I also use 3rd and 4th going hwy speeds because that's fun, but when I do I get 17mpg or under 50/50 driving.

My mpg just took nose dive recently since the change in temp :(

getting about 15 mpg instead of 22-23 before

claude, why did you round down from 13.92? It's a heck of a lot closer to 14 than 13. Anyways, even within the same model individual cars behave differently. Some will take a while to settle down, so give it some time.

Pyrospawn's observation is very important for the rest of us. He is a single individual who has observed both ends of the spectrum in ONE car. Furthermore, his car was getting pretty high mileage, indicating the engine in his car is not a lemon.

Others have hypothesized that low temperatures may have a negative effect on mileage but those, to the best of my recollection, were across different people with different cars.

Do piston engines see a cold weather dropoff in mileage? If they do, is it as drastic?

Can a rotary owner do anything to counter the effect (e.g., longer warmups)?

Claude, if you remember me, I too got my car from Country Mazda in Huntington. Glad to hear you're enjoying your car.

I am getting between 18-19MPG on my car, and I travel the LIE everyday. I just passed 3000 miles.

Hey RX8Lover,

I knew you were lurking around here somewhere. I love this car. It really is a peice of work and seems well thought out in so many ways.

And to all you others on this thread, hello and thanks for your input.

RX8Lover, you get only 18/19 with mostly hwy driving? How about around town?

Don't get me wrong guys, I never expected to get mid 20's MPG here, however I would like to get 20+/_ driving about town in a normal, if somewhat spirited, manner.

As I am just breaking in the engine, I am not pushing it and haven't even passed 5K revs yet. Although my right foot is beginning to twitch a bit to see how it feels hititng 7 or 8K+.

How long do I wait tilll I can run it up a bit and be safe with the engine? 600 miles or more?

So my millage is absed on driving mostly around the 2.5 to 3.5k rev area.

Thanks again guys.

Claude H.

Life on the LIE isn't exactly highway driving, as more often than not it is a parking lot. But I do take the HOV lane, where I usually cruise at 70 in 6th gear. However, I won't lie and say that I never go to 9000 rpms...I do, many times. The engine revs so easy all the way to redline that I can't help but do it, plus it's fun. I didn't start getting on the engine until 1000 miles.

I think this engine runs richer than it has to, but thats just my opinion.

Boy some of you are tough.....Buy a Civic....not necessary to state that! We just want something close to the stated mpg. 12.5/13 mpg city to me stinks and I would be happier if it was at least around 16/17 range which is below the stated mpg. I love the car but I hate having to constantly worry and look at the gas gauge! I am not expecting too much just reasonable gas mileage.

On both RX8's, I have consistently gotten in the 18-19 MPG range. I think the lowest I ever measured was about 17. First car had about 4K on it when I returned it, new one has almost 2K miles. Mostly, I commute in the SF Bay Area (highway 880 for those who care). The milage is slightly better than my 91 RX-7 convertible, and slightly worse than my 82 RX-7 (from what I remember). It is definitely better than the 12MPG I get in the Durango. When they do the measurements to determine highway milage, I suspect it is running at a constant speed of 65-70 MPH for long periods. What I see is that my morning commute is anything but constant speed, driving anywhere from stop-go on the freeway to significantly over the speed limit (but going with the flow) for short periods of up to a mile or two at a time. Coming home, I have hit significant speeds (I come home late with little or no traffic), so I am quite happy that I am getting 18-19. Even the one tank I had that I was able to cruise for a large part of it at 90+ got me 18.

Of course, if the fuel milage was really a problem for me, I would drive my wife's Prius :).

Oil viscocity affects gas milage in piston cars, not sure on rotaries, I'd expect the same though. Thicker oils tend to produce lower gas milages, possibly because the pistons have to fight the thicker viscocity harder in order to produce the same amount of output as a lower viscocity oil. Lower viscocity oils have also been known to produce a few extra horses on the same car. IE: 20w50 VS 0w30, the 0w30 tends to put out an extra 2-3 horses on a chassis dyno.

In the winter, the oil isn't as...fluid-like due to the coldness, so with that said, I suppose it is possible for it to affect engine performance, which in turns, effects gas milage.

I guess I am lucky,normal and just right. I average 18.4 - 18.9 in very mixed driving even short trips around campus 2 miles around. I check every tank. More fun = less mileage but in tenth's not gal. If your mileage is in the range of 12 mpg you have a problem. I would plan a trip fill up get on the freeway where you can go unheeded set the cruise on 60 and go 150 - 200 miles. Stop fill up and check the mileage it should be over 20 mpg. If it is at 16 - 17 mpg you have a gas hog. I would have the ECU checked at the Dealer. Mine would be replace one way or the other. This car loves gas but it's not a hog. Also check your tire pressure. The higher it is the better mileage you will get.

i dont know about the rx8's...but i do know that most people start reaching their optimum gas milage when they are a couple thousand miles into their engine and its fully broken in. I know it took about a thousand miles on each of my motorcycles to reach optimum milage.

Ways to improve mileage
 

The Rx-8 has relatively large and heavy rolling stock. i.e. a lot of inertia and rotating weight in the wheel and brakes. I would venture a guess that smaller wheels or forged aluminum lightweights would do something for both gas usage and Wheel horsepower. Have you ever seen what happens on the dyno when a car get's "upgraded' to bigger(heavier) wheels? The power drops in measurable amounts and that mean the loss of mileage and power. I love the look of big wheels too, but that is the price you pay. That's one reason why honda and toyota have been so conservative on wheel sizes until lately, and many of the larger wheels are of a lightweight design. I am planning on some forged aluminum wheels in the 13-15Lb range, and I expect to see a gain in acceleration as well as mileage. The 93' RX-7 had lightweight 16" wheels and it pulled 1.00G on the skidpad. I see no real need for large heavy wheels, and they do far more harm than good. I wish I could go to 16" wheels, but the brakes probably won't fit, and the wheel wells are too big. They would swallow the 16" wheels up!

Ya...the brakes are freaking massive, I think that even dropping 17's into there would be extremely tight to find a set that would clear the rotors properly.

I am on my fourth tank of gas. On the third tank I filled it with regular as compared to premium. I did this as an experiment to see if my RX got better mileage on regular gas as opposed to premium (this has been discussed on another thread). I drove 203.1 miles and with one tick mark below 1/4 full, I filled it with 12.303 gallons of gas giving me 16.508 miles to the gallon on strictly stop and go urban loop driving with only one 10 mile loop of interstate driving. On my first and second tank I did get noticably worst gas mileage (13.2) with the premium as I was only able to get 170 miles or so out of it before needing to fill up. I so far am happy with the gas mileage I am getting. I do not flog it as some might do but I drive it they way I want to enjoy it.

Rotary Nut? How many miles do you have on your car now? I'm curious as if there is a significant correlation between miles driven and gas milage.

869 miles and still lovin' it!

We have two RX-8s. Both are base model 6MT... no frills. I have 5100 miles on mine and my wife has 3450. I get 275 to 300 per tank and normally pump in 14 to 14.5 gallons. My wife gets slightly lower mileage. I have noticed that she stays in 2nd, and 3rd longer than I do.

Both of us drive 60/40 highway/city... highway speeds are 80+ 6th gear at 80mph is just over 4k.

Agreed. The advertised numbers are not even close to the real world numbers. Is this common among manufacturers?

Lower than advertised HP, lower than advertised MPG... geez I think I'll sell my 350Z and pick up one of these mean machines.

Always good to hear from the Z mafia....

Everyone wants to compare these cars and they are built for completely different demographics groups. Interesting how I do not see many BMW 325 owners bad mouthing the 8.

If we have to continue to listen to Z-whining can you all just let me know when you figure out
- where your two missing passengers are going to sit
- why you have to pay for upgraded brakes and wheels
- why you have a smaller less usable trunk
- why you have to pay extra for a limited slip rear end
- why you have to pay extra for front side air bags
- why you have to pay extra for Side Head Curtain Airbags
- why your basic warranty is less
- why your 0.86 skidpad grip is worse
- why your 163-foot 60-0 stopping is worse
- why Car and Driver picked the RX-8 over the 350Z

And finally, why your car is just not as cool?


:D

jeez, is that all you got? More expensive options and stopping distance? Bigger trunk? Are you serious?

None of those things were even on the radar when I picked out my Z. I wanted a bitching sports car, not a series of lame compromises.

Just let me know when you and three friend get back from taking your bitching sports car down a nice winding road. Gonna be damn cramped and hard to shift... but maybe you are one of those wannbe Z drivers with an automatic...

and I don't see better stopping and better as a compromise... I just see it as better.

Don't feed the trolls!

:(

Sooorrry.... sometimes ya just want to toss them crumbs....

I promise not to tap on the glass.

;)

Ok...just was chatting with an older gent(about 60ish) while i was getting gas. Conversation went like this......"I bet your having fun in that car" I said yes I am. He said, ah, the rotary engine, great car! I said yes but it's a gas guzzler. He said yea, it's all about performance. And then he said "well, it will get better...the engine has to break in a bit....it may take as much as 12,000 miles before it breaks in." I said, well I will have the car for longer than that! He went on to explain to me why it is getting poor gas mileage right now and how the gas is lost through this and that and through the exhaust system, etc. And so as he admired the car I felt a lot better about it all. He seemed to know a lot about the rotary engine....thinking he must have had one or read up on one in his past. He was driving an old Olds Toronado. Ok...just thought I'd share the story for all who are worried about the mpg!

I just got my car, and I am getting 18mpg with 300 miles on the odometer.

Good for you 8er4lunch!! Man, I hope to get that kind of mileage soon!

wow, nissan quality, harsh ride, room for 2. geez, I think I'll sell my 8 and pick up one of these.

honestly, you're a tool. :D

As far as I know: The 'advertised' mpg numbers were determined by EPA, not by Mazda!

18-23 right? 23 would be under ideal conditions, downhill with the wind pushing you :-)

Just kidding, I'd think that there is a definition of what is normal. That definition would include air temparature, wind (absence of..), and probably even altitude.


That said.. my previous car was a 2000 Firebird. Advertised with 19/29 and I usually got 26 or 27. My gf had no problem getting the advertised 29 and even more, simply by following the speed limit. The automatic transmission in that car allows going 65 mph at a smooth 2000 rpm.

--> EPAs numbers can be achieved in real life.

--> Mazda definitely is not to blame. It's our driving style.

-Peter

*click* <---- sound of my mouse blocking a user

I routinely get 21-22 mpg, driving 80 miles daily, with 80% Highway. Interstate driving I get the 24 mpg that EPA estimated for the RX-8.

Octane between 93 to 89 offers negligible difference in mileage. 87 octane seems to give a little better mileage (+1 mpg), but prefer to use higher octane to reduce knock potential, since I regulary load the RENESIS with quick starts & high revs.

I routinely get 12-13mpg and don't give a flaming crap. 90% of my driving is local, short commutes.

In a WRX, I get 13-15mpg.. in my STi V, I get 11. My friends who drive new STi's in the same conditions? 14-15mpg.

However, once you get the car on the highway? I can easily pull 20mpg.

Claude-

gald you got your car. BTW that was your silver with tinted windows I saw parked on 74th street, a week ago?


ANyway I am convinced that NYC area driving is unlike many other areas, and that the car just gets bad milage with short trips, ideling, stop and go , etc. I am still in the process of getting my 8 fixed up and sent back to Mazda. I am thinking using my Probe GT for the winter months and getting a new 8 in march. WHo knows, maybe by that time they're will be some new factory issues they improve upon. If not, I guess I'll have to focus on making more money to pay for gas and the smiles the 8 brings- even though she is one thirsty beast!

All-

Sorry for being the bearer of bad news, but I have never averaged more than 14 mog, have nearly 6,000 on the car and ahve complained to Mazda 8 times. Yes, 8 times.

Got a response yesterday after sending a certified letter to Mazda NA. They said - sue us under the Lemon Law becuase we will not reconsider.

I should have taken the buyback. I feel like I have been totally screwed.

Hi emailists,

No my car is Titanium with no tint. I have nauticcal code flags on the rear quarter panel with my initials.

I love this car and only hope the MPG improves.

This car seems so right in SO MANY WAYS!

Who knows, maybe Mazda will release an ECU upgrade soon that will correct, amongst other things, the MPG issue.

Any rumors you hear to this fact?

Claude H.

Mazda gave you your out. Too bad you are unhappy with the path you chose.

Highway 20 possible. No highway, you' get 14-16. That isn't close to what was advertised and I think there needs to be a recall.

Ya know this just never stops. I do not know why some folks are getting lousy mileage. Whether it is their driving style, the type of route taken (city/stop and go...), the gas sold in a particular area, or maybe the ECU and gas mapping out of adjustment.... obviously there is something wrong. Having read several responses, there are a lot of folks that do not drive their cars the same way it would be driven in a mileage test. I also note that a lot of the mileage problems are in California and the northeast. Both these areas sell reformulated gas and corn gas.

Whatever the root problem, I think Mazda should be more open and work with the customer. But until you can show a design flaw that can cause some to have a problem and others to function perfectly well. There is no basis for a recall.

Lastly with two 8s, we do a lot of comparison and if memory serves me, the mileage advertised was 18/24 well that would average to 21mpg with a wimpy driver. I drive more aggressively than most of my friends and getting 20.5 to 22 on most tanks. There are times when I screw up and sit in 5th at 85 and this will knock the mileage down. My wife drives in 3rd and 4th more than I do and here mileage is slightly worse. With this said, there is no way I could justify a recall.