One raison to explain the relatively low MPG of the 8 is that: back in the days this car was launched, Mazda was not the best at fuel economy, whatever the model they proposed to public. And in most cases their models were the worst in every category for MPG. That's why they did their homework and try hard for many years to address this, so they came with the SkyActiv technology, which is great.

Obviously, Skyactiv was not created for the rotary (apart for better transmissions) but for conventional pistons engines. Add the fact that the model was almost 10 years old and sales were at their lowest... the rest is history.

We hope Mazda have project to adapt Skyactiv (or Hybrid) to the rotary and launch a new model for the 50th anniversary of the first Wankel-powered Mazda. Finger crossed!

I just have my RX8 for 2 days, so I can't tell much about my mileage with certainty. I filled the tank with 19 liters when the fuel light was on and drove 160km until it came up again, which is roughly 20mpg.

With my previous car (Mazda Lantis) I got between 18 and 30mpg, and considering it weighs 30% less and has a third of the power of the RX-8, the RX-8 is more efficient.

I learned that attitudes towards gas prices are very relative aswell, so I don't want to be too much of a dick about that, but the RX-8 is still worth it for me.

My last tank I got 24.35mpg, my friend in Canada tried to disprove being able to get 400 miles on one task of gas. Well he failed and filled up his car at like 403 miles, which yielded him 29mpg I believe is what he said he filled up at.

This is how he did it:

One start only
averaged about 55mph
Windows up
No air conditioning

His cars modifications

Intake
Midpipe with stock muffler
Sohn adapter


https://cimg5.ibsrv.net/gimg/www.rx8...cd0ff1a55e.jpg


Now for my daily driver rx8

I go roughly 300 miles averaging about 65mph
I do close to 40 miles under 40 mph
I have about 20 starts to tank
I use my air conditioning for about 200 miles every tank
I pass a car or two at probably 90-100 on back roads

The tanks you see where I get about 18mpg are very spirited driving and lots of fun, the tanks 23 and 24 have zero fun at all. The tanks around 20 are fun and normal driving mixed.

My cars modifications

Intake
Gutted cat
Second resonator
No mufflers

https://cimg6.ibsrv.net/gimg/www.rx8...54a593f550.jpg





https://cimg8.ibsrv.net/gimg/www.rx8...3613185ed4.jpg


https://cimg9.ibsrv.net/gimg/www.rx8...464eb74513.jpg

Could you tell us more about the driving style? What RPM range, how fast, how much city/highway? This is incredible.

Well the guy that hit 29mpg set out to do that, his was 100% back roads using a ton of hypermilling techniques. He does live in a hilly region as well.

As for me I listed the best I could the areas I drove it. Anything under 40 is in town driving. I might map quest my normal drives do people can see what kinda driving it is

My style of driving is keeping the rpms under 4k, you don't need to rev the piss out of your engine every single time you shift. The only place that carbon can build up in engine is on the rotor face and the spark plugs themselves. Every few tanks in give her a nice tromp through a few gears. I never have any black smoke or missing.

I daily drive my rx8 and I put a lot of miles on, so It only makes sense that I would try and squeeze some factory numbers out of the mileage. Yes I didn't buy it for mileage, but when I spend a lot of time with cruise control on its hard to beat on her lol.

I got like 200 quarts of Mazda ATF for like 80$, I premix with it. Not really looking to debate it, because it's a debate that never goes anywhere on either side. ATF and 2 stroke are made from the same base oil, also my car loves it.

I bought my car for it's driving style and power aswell, but I'm not going to rev it on a 300 mile distance non-stop. It's fun at traffic lights to rev through the first, and sometimes 2nd gear when entering the highway, but otherwise I just shift it into 6th gear when I cruise, pretty much anywhere.

I even drive in 6th gear when I'm driving 30mph, but I could believe that 4th or 5th gear could be better and more economical. Much like a 1.5L engine car would have a worse mileage than a 2,5L engine car because you would need to constantly drive with full throttle when going uphill with the 1,5 whereas the 2,5 does it with ease with maybe half the gas. But correct me if I'm wrong.

It's much like racing a Prius on a racing track which is followed by a BMW M3. The Prius turned out to be less economical than the BMW M3. City driving in an RX-8 is bad for the economy, but on the highway it comes to its right.

TomX8 you are just making more carbon deposits if you just keep the revs low in sixth gear all the time. You may be saving gas, but you are not saving your engine,you are hurting it ! Wide open throttle ,every now and then (with a fully warmed engine) is best for a healthy life for your engine internals. (less carbon buildup)

I think people should look into what actually causes carbon deposits in engines, that'll help people under stand what's happening better.

At 103k miles I swapped my engine and transmission with a engine and trans that only had 30k miles. This set up was in a totaled car in the back of a semi trailer for over 7 years. I had to actually push start my car to get her to run.

I'm now turning 109k miles and have average 22 mpg across the board, my carbon build up on my rotors has decreased significantly since I first checked it. Every few thousand miles I pull plugs to check the rotor faces and condition of the plugs.

I ran straight piped for the first few thousand miles, just a few weeks ago I went back to stock intake and stock cat. Drivability is a touch better and I will be pulling my cat every few months to check its health. Which so far is a beautiful silver.

Mod Edit: Remainder of post removed until you are a registered vendor.

That's the point of why gas mileage and the rx8 do not belong in the same sentence. It's not a economy car. I red line mine at least 3 or 4 time each time i drive it. The phrase " Drive it like you stole it" is no joke when it comes to the rx8.Fuel economy attempted by a driver is indeed a death sentence for a rx8 rotory: This thread should be called "How to kill a rx8 forum". lol lol.:eek:

I pull my plugs every oil change and inspect everything.

I turn the engine over so I can look at each apex seal and check for carbon build up on the sides of them, I also inspect the rotor surface compared to the previous oil change.

My engine sometimes goes 500-800 miles without a single full throttle or beating, and I can guarantee that mines cleaner them most of the people out there.

You don't need to rev 9k to prevent carbon from building up, you can shift to 4-5 getting on the highway and that's good enough.

There are many variables obviously and premix is the big one, chose a premix that burns cleaner and at a lower temperature and that'll help big time.

I am confident you have paper work to back that claim up? right?, please post it , i would like to read this proof:icon_bs:. , other wise this is your opinion . Every one has one few have any back up. As i sad i rev mine to red line every day and i have 101,000 miles today and that doesn't mean i am right it only means the car didn't break and it also runs like new but that is my subjective opinion. Thats the issue at the rx8 club , mostely opinions and no back up. In fact some partys here have made political currency here based on opinion and having 5,000 posts seems to some how equate to knowledge? Who knew? LOL:).

Paperwork to back up what? My own work lol. Wouldn't that just be a biased piece of paper seeing how I'm the one who would be filling it out?

There is no set way to document and of the above, because no matter what you do someone will claim its bull shit or fake.

Putting it that way i would say true that:wiggle:

Cumulative Gas Mileage (Gas MPG) Thread
 

How will you guarantee this? I'd like that proof, or my money back...

That would require you to spend money first wouldn't it? :)

I guess that my guarantee would be more or less me running my mouth ha.

I'll provide photos of the rotor face and plugs next time I pull them.

Remember the rx8 is not an economy car. On every day driving my guess is you would be lucky to get 20 mpg on a consistent basis, and if you drove it like grandma, soon you would need a new motor from carbon buildup. A gas mileage discussion on the rx8 is kinda silly.

The rotary engine gets the most of its carbon build up at idle, a engine doesn't have to reach red line to "burn off carbon" it only needs to have enough internal heat built up that it burns off the carbon as well. With that being said you could be going up hill in a lower gear and create enough heat to burn out the carbon as well. There is no real evidence out there done in a controlled study that says getting good mpg with a rotary engine will wreck it, anyone can take a part a motor and say anything they want.

I document every single tank of gas I get and my mileage, if and when my engine goes out I'll post picture of the internals for speculation. But no matter what documentation I have or pictures it's all just speculation.

Also just because someone wants to get a few good tanks of gas on a road trip or during the week when they are going to work doesn't mean they are going to wreck their engine. Carbon build up on the rotor surface itself really isn't the issue, it's carbon build up around the side seals and the apex seals that becomes the issue. Over time enough gunk could cause the apex seals to stick and either prematurely wear or cause a loss of compression between two sides of the rotor.

I hope I neve have to take the engine in my daily driver rx8 apart the whole time I own this car, but if I do I'll share whatever I find in hopes that wether I'm right or wrong it will help someone else out.

I've managed to get about 20/21 mpg on purely highway driving, which I know isn't exactly all that impressive. In the city it's DRAMATICALLY lower. Usually 13-15 mpg. It's pretty cool to see someone getting such high mpg though.

Bottom line is that the rx8 is not an economy car period. Any claim to mileage is , well not really important given the small sliver of so called MPG range the rx8 is capable of ?.

When I first got the car I was averaging around 18mpg, running the A/C and driving like a pissed off teenager

Better driving habits yeilded around 20-21mpg

I started using Lucas Upper Cylinder Lubricant as premix, and I am consistently getting around 23.5mpg with winter gas and 240lbs of weight in the trunk.

No modifications. Approximately 15-20 starts per tank. I let the car warm up for 5-10 minutes when it is below freezing. Can't complain, does better than my truck lol.

Got 15-20 pretty regularly

Why do you always make a fool of yourself?
This thread is about people posting their mileage; not condemning it (mostly, anyways).
Focus on thinking before you type, and then reading what you type to ensure it has anything to do with the topic at hand, prior to hitting that 'Post' button...

You need to stay on TOPIC. Any contrary comment does not qualify one as a fool.Bashing another here is not adult behaviour , stay on topic please.:scratchhe

I get about 8MPG and it is worth every penny.

If you want a different point of view on MPG check out the thread titled " How to get the best MPG on the rx8 ". I read the whole thread and i came away with two things: !) The rx8 wasn't designed for economy ( My 04 series one automatic gets average 20 MPG). 2) It is interesting to see how when this older thread was written ( 7 or 8 years ago ), how the low attitudes changed as the post counts rose in number. As post counts rise you can see the snarkey ness of some got worse. For me the end result is yes there are some things one can do to increase your MPG with k&N filters and driving habits, lighter wheels and lighter batterys etc but at the end of the day acumulative gas mileage is a rather moot point in view of the fact when you delve too far into MPh efforts you do sacrifice the fun of the car which is the pure fun of unbridled RPM and the cars handling efforts. My 2004 series one automatic does get an average of 20 to 22 MPG with out any sacrificing of the pure fun of driving the 8. In the thread titled " How to get the best MPG on the rx8 " some one made the comment that trying to get high MPG out of the rx8 was like arranging deck chairs on the titanic lol , and that is my point. I am only stating the obvious , the rx8 has a average of 20 to may be 22 MPG and maybe 10 to 15 MPG if you track your car. The car wasn't made for ecconomy , it was made for fun and i for one after 110,000 miles love the car even more than i did when it was new :).