Make sure you tire pressure is at least 32psi on all tires, shift at 3 to 3500k, not BEEP! Or skip gears. 1st, to 3rd, to 5th. or so. Whatever floats your boat. Its worked for me. I do 80% city driving and avg 19mpg, but still have fun! BEEP! When I do nothing but hwy, I have gotten a amazing 29mpg. It can happen.
I also log my info on https://www.fueleconomy.gov/mpg/MPG.do

Q and A:
What have you all been getting and in what driving conditions??

Make sure you tire pressure is at least 32psi on all tires, shift at 3 to 3500k, not BEEP! Or skip gears. 1st, to 3rd, to 5th. or so. Whatever floats your boat. Its worked for me. I do 80% city driving and avg 19mpg, but still have fun! BEEP! When I do nothing but hwy, I have gotten a amazing 29mpg. It can happen.
I also log my info on https://www.fueleconomy.gov/mpg/MPG.do

Q and A:
What have you all been getting and in what driving conditions??

I didn't buy an RX-8 for fuel efficiency...but I know that keeping the RPMs low (2-3g's) makes a HUGE difference. Someone was saying about getting more mpg after putting more miles on their cars...I bet it's just that after a while they learn how to drive it more efficiently. I know I get way better milliage now than when I first got the car... :cool:

gas mileage tip #2: lay off the gas.

gas mileage and power output get better on rotaries as they get past their infancy

this is normal gas milage for me, my first car was a lt1 v8 trans am, then my winter car is a 91 tempo ... noth had the same gas milage. so the rx8 getting 300+km on a tank of gas is amazing for me!!

32's the way to go

Oy. That's the maximum tire pressure. For the proper recommended pressure for our application, check the plaque inside the driver's door jamb. It lists 32 psi.

Er um. I like checked the Potenzas pressure rating yesterday. It's 51 PSI man.

32 PSI would be awfully low.

Thanks btw I was wondering how to bring up that I noticed they were 51psi and all low :P

- :)
WTF!! 51 psi? your crazy. that has to be terrible for your tires.

umm.. skipping gears bad for synchros, no?

The only why mine gets better then 12mpg is to let it sit in the drive way. But al least Mazda is ignoring the problem. :rofl:

side note: i went through 1/4 tank and managed to drive 67 miles mostly highway. my gf's toyota highlander (i understand the tank is bigger but not by much) drove the same distance and the gas needle moved only a tick.

umm.. skipping gears bad for synchros, no?

i usally do 4-6 on the highway. up until last week i never really used 5th. but now i normally don't skip gears anymore unless im downshifting

My gas mileage sucks. I get about 13-15, if I'm lucky. I had heard that shifting it at higher rpm's would help some. My tires have 32psi in them. What's funny about that is that when I bought new tires, that's what they put in them. I took the car back to them because I had a flat and it had damaged the tire. They said that they wouldn't honor my road hazard warranty because I wasn't running 45psi in the tires. I've never heard of running that much in these tires. Heck, who knows.

My gas saving strategy is called: Chicago Transit Authority

After that, I've been at a consistent 17.5mpg since I bought the car. I'm at 24.5K.

Tip #4: park in garage and don't drive

^ NY's MTA... just hope they don't organize another strike.

Tip #4: park in garage and don't driveYup...I do that one too. Drive the Tahoe. It actually gets better mileage on the highway than the 8. Hell, my LS1 Trans Am got better mileage than the 8.

I'd been wanting to ask this, is skipping gears ok!? I mean a lot of times I have no need for fifth on road trips, by the time I get to a good speed in fourth and I'm ready to put it in cruise, there isn't a need to go to fifth. I was just assuming it would be bad on the car to skip the gear.

I'd been wanting to ask this, is skipping gears ok!? I mean a lot of times I have no need for fifth on road trips, by the time I get to a good speed in fourth and I'm ready to put it in cruise, there isn't a need to go to fifth. I was just assuming it would be bad on the car to skip the gear.
As long as you match the revs when skipping 5th, I dont see how it could possibly be bad.

Gas tip #5: Buy a car thats meant for mileage, not spirited motoring.

As long as you match the revs when skipping 5th, I dont see how it could possibly be bad.

I'm with you, I skip gears often...at least for casual driving.

And downshifting gets those rpms up there...this is more gas consumption. ;)

After 22k miles I have finally learned the secret to getting decent fuel mileage...I quit driving it like it's a go-kart all the time. The car is just so much fun that I have a hard time going through a tank of gas without spinning it up to redline a couple of times and taking turns hard enough for the DSC to kick in.

Now that the initial rush of ownership has subsided I find that I can limit my trips to the red line to maybe once a tank. And the cost of replacing that first set of tires has helped me limit those eight-tenths turns.

Guess I'm getting old.

Repost

Yeah, I definatly match rev's when skipping fifth, that's a huge sigh of relief, I was so worried that was going to kill my car completely.

The only why mine gets better then 12mpg is to let it sit in the drive way. But al least Mazda is ignoring the problem. :rofl:

Raptor:
I've been following your saga of horrible gas mileage and was wondering: Have you taken your car on a road trip yet to see what kind of highway mileage you get?

Just curious as to whether your highway mileage also sucks...

I bought my RX-8 from Autobarn at about the same time you did, but I'm getting 19 mpg in city driving.

i live in FL, anytime is over 80*F or really humid I run the AC on recirculate fan setting #3. So thats about April to August that I use the AC when I drive. I shift at 4k most of the time driving in the city, and cruise in whatever gear I need to so im always around 4k rpm so I have power......i rarely use 6th unless im on the freeway, I use 93 octane shell/chevron ONLY and run a fuel system cleaner every tank and a double dose every oil change. I also pre mix 2cyle syn oil in with my gas, at a 400:1 ratio.

On top of all that I redline gears 1, 2 and 3 all at least once everytime I drive the car, change my oil/filter ever 3k with castrol GTX and change my spark plugs ever 10k miles along with cleaning my K/N drop-in filter. My car runs well, its pretty peppy and I get 18-20 mph city. I drive 250 city miles PER WEEK and rarely use the highway. Most of the time I get 19.5-20 mpg, occasionaly I get 18-19, and I have never gotten less than 17mpg......so thats where I get 18-20mpg from.....

cheers

I'm with you, I skip gears often...at least for casual driving.

And downshifting gets those rpms up there...this is more gas consumption. ;)

down shifting is only using gas when you rev-match.

whenever you coast in gear (engine braking) you dont use any gas.....so coming up to a stop, if you shift into neutral and use the brakes you use the gas to idle the engine, if you just let off the gas and then put it in neutral when you stop you got that distance for 'free'

I only downshift at the track, but I do let off the gas and coast in gear up to stoplights, using the brakes but leaving the car in gear till I just about come to a stop.

Make sure you tire pressure is at least 32psi on all tires, shift at 3 to 3500k, not BEEP! Or skip gears. 1st, to 3rd, to 5th. or so. Whatever floats your boat. Its worked for me. I do 80% city driving and avg 19mpg, but still have fun! BEEP! When I do nothing but hwy, I have gotten a amazing 29mpg. It can happen.
I also log my info on https://www.fueleconomy.gov/mpg/MPG.do

Q and A:
What have you all been getting and in what driving conditions??

Erm. Gee. Thanks. Really. Have you checked out any of the other threads about this yet on here? There's only a few thousand.

Are you SURE you got 29mpg? People doubt me when I tell them I went 310 miles on one tank (13.5 gal before someone starts in the "YOU CAN'T MEASURE BY TANK" junk)before the light went on, once, and that wasn't anywhere close to 29 mpg. More like 24mpg. I'm not trying to call you out, by 29mpg? You'd be getting what, something like 400 miles on a tank? I've never heard of anyone doing that before.

Yeah, I smell BS.

hmm well i hav emade over 24. recently brilo made 27mpg on a trip. 29 is stretchign credulity tho

On top of all that I redline gears 1, 2 and 3 all at least once everytime I drive the car, change my oil/filter ever 3k with castrol GTX and change my spark plugs ever 10k miles along with cleaning my K/N drop-in filter. My car runs well, its pretty peppy and I get 18-20 mph city. I drive 250 city miles PER WEEK and rarely use the highway. Most of the time I get 19.5-20 mpg, occasionaly I get 18-19, and I have never gotten less than 17mpg......so thats where I get 18-20mpg from.....

cheers

you and your flat state :p:
although, i'm not too far off that. 17-20, with a 50/50 mix of driving...although i don't know if those highway miles should really count as highway miles, as most of those are in stop and go gridlock.

Always 20+ mpg regardless, but never more than 22 even on highway trips. It's hard to run 72 mph around here without getting run over by an SUV or pickup.

37,000 Miles
12/03 Build Date
Only 93 octane Ammoco Ultimate
Castrol GTX every 3000 miles
Latest "hot" plugs from mazda
Racing Beat Exhaust
Green Drop in Filter
245/40/18 BFG KDW 2's

Ok, I give up. can someone explain rev-match to me.. please :)

Thanks

Ok, I give up. can someone explain rev-match to me.. please :)

Thanks

when you downshift a car (say go from 3rd to 2nd gear) if you just put the clutch in, change the gear, and let the clutch out, the engine will be forced to quickly speed up to match the speed of the rest of the drivetrain, so when you rev-match, you 'blip' the throttle so that it speeds the engine up, that way when you downshift and let the clutch out, the engine is already at the speed it needs to be at.

Also in older cars, before manual transmission had syncros, you would have to match the engine rpms to the gear you want to go in, so that everything is spining the same speed.....

"REV-MATCHING:
When taking off from a stop and then going up through the gears, steps 1,2,6,7 above are the normal shifting method for each gear change. The synchro-mesh are more than enough to control the intermediate shaft speed. The engine will passively rev-match itself because it slows down naturally and this is appropriate when shifting up.

When down shifting, the engine needs to spin faster as it engages the new gear. This can be achieved by 'blipping' the throttle as the transmission passes through neutral. If the engine isn't manually sped up by the driver, it will be sped up by the driveline when the clutch is re-engaged. This can be OK for normal street driving, but if the car is cornering near the limit this can upset the suspension and the tire adhesion.

The synchromesh are usually adequate intermediate shaft control when down shifting one or two gears. Aggressive downshifts (like a 5 - 2 shift from high speed) can benefit by using double-clutch shifting to assist the synchro's. Shifting into first gear in a hard corner is nearly impossible without double-clutching (this is useful for those really tight hairpins, especially if they exit uphill). "


hope that helps

Today, was my best tank ever! 17.2 mpg! That's amazing! It was about 90% city. Normally, I do all city and I get 15 mpg. I was at about 240 miles on the tank. Normally i get about 208. Something around there.

I got tanked last night at the Green Lantern

When I had the patience once, and the chance to drive in the slow lane with the trucks I did get 29.5mpg. It was doing 55-60mph for two plus hours. It is very hard! I got 27.5mpg twice doing 65mph. I use the cruz.....and have AT.

About the only startling thing in this thread is that people still think 32psi is right because the manufacturer's placard says so.

Personally, I use 36-38psi for urban driving and boost it to 40psi when on a long freeway trip.

If anything, lowering the psi will increase fuel consumption.

As for the fuel tip - gee, if I don't rev the car I'll save fuel?? Really?? Thanks. I NEVER would have figured that out on my own. :rolleyes:

I calculated yesterday when filled up and I was at like 285miles on 14.5gals. It was like 19.8 ml/gal. I also probably ate up a couple of quarter tanks in displays that are known in these parts as "exhibition of acceleration." :nono:

:)

doesnt matter how hard or softly aka granny I drive my rx8, always in the low 20's. Usually 21-23. Long trips where noone pisses me off, and I'm not in a rush and I keep my foot out of her, I've gotten 27.

40,000 miles since april 1 05. my lifetime mpg is 21.06 :)

Octane doesn't matter either, I actually tend to get better mpg on 87, but it MUST be good QUALITY gas. If it fill up with the cheap no name crap, my car runs accordingly. It still get good MPG, but it's retarded feeling, it's not smooth and happy, it's clunky and slow.

I'm thinking 40 psi in the tires could wear the center tread section out prematurely, not to mention ride quality would have to comparable to that of a covered wagon, especially if you have aftermarket springs. I could be wrong, though.

I'm thinking 40 psi in the tires could wear the center tread section out prematurely, not to mention ride quality would have to comparable to that of a covered wagon, especially if you have aftermarket springs. I could be wrong, though.

You're wrong. :)

Seriously, ride quality does suffer a little, which is why I reserve 40 for long trips on decent freeway.

However, wear is even.

90% of motorists don't have enough air in their tyres (this from a number of experienced defensive drive instructors, all of whom have advised 30-32psi is too low for a family sedan let alone a performance car with low profile rubber).

well, er, I'm brand new here, just bought a few days ago. And while its difficult to guage how much gas the dealer actually put in the car and other intangibles, it looks like I got about 16mpg on my first tank (and I was driving like a grand-ma!!!.......haven't even put the car over 6K rpm yet)............ugh...........................

I decided to granny drive for a full tank of gas to see what I could squeeze out of mine. I stayed below 3500 RPM (except for a few minor falls off the wagon) and moved as slow as possible trying not to press the accelerator any further or faster than required to stay up with traffic. Man I pissed off a lot of pick-up trucks. If I had gone any slower, I would have had to speed up to slow down.

I filled up today and got 17.3 MPG. That's approximately 70% city and 30% Interstate. I normally get in the 14-15 range if I'm lucky.

I don't think I can keep this up because I really miss beeping and listening to my RB exhaust. With the price of gas going through the roof, that gives me a little more incentive to poke my way to work.

hmm well i hav emade over 24. recently brilo made 27mpg on a trip. 29 is stretchign credulity tho

what mph were you guys crusing at?

21-23 mpg hilly country roads shift at 5 - 8 k. 1/3 throttle and wait for rpm's to peak when accelerating, coast downhills. 25,000 miles on 2004.

what mph were you guys crusing at?

72mph in 6th. That keeps the revs right around 3750, and the other intake port kicks in at 3800 (so I'm told). This routinely gets me about 22mpg on the highway. Its a 2005 GT running mid-grade gas (89) and with about 3k miles on the clock. Round the city, I get 16mpg typically.

My best so far was 23 mpg... All highway, ~75 mph, flat terrain, cruise control, ~85 deg F ambient temperature, Shell 93. Typical around town is 17-18 mpg.

I think cruise control is a very crucial factor in getting good gas mileage.

My last long trip in my 8 I got 24.4 mpg. Cruise control and 70-75 most of the way, some 80's. Normal driving in my area I get 21-23. I haven't had a tank under 20 since before the M flash. And yes my fuel economy seems to be improving as I get more miles on, even though it currently has only 13,000. :)

Shifting at low RPM is a goodway to carbon up your apex seals which will cause big problems in the future.

The majority of the time I shift it at the speeds recommended by Mazda in my manual which comes out to around 2750 RPMs. Although, when I pull out off the detour road onto the main road I just pull out and keep accelerating and shift right into third so the RPMs get up over 5000s. I will also do that when I have to merge with the traffic from usually a stop to get onto 213, so if I shift at all the "recommended" spots my arm is either moving constantly or I'm not accelerating fast enough to avoid pissing off the other traffic. There I will usually just pull out and keep accelerating and will also skip gears to keep it smooth and it also gets the RPMs up. I use my cruise control on the way home from work but it's hard to do it on the way to work for more than just a few miles because the traffic speeds keep changing so much. I also can't use it on the country roads as their speeds change often and there are also a lot of curvy stretches you need to slow down for (just a tiny bit, unless there are other cars and they you pretty much crawl), so it just makes it really hard to use it all the time, but I do use it whenever I can.

what mph were you guys crusing at?

Got 23.39 mpg (11.5 gal fillup for 269 miles) this past week driving home from the beach. Spent most of the time on cruise at about 65mph. The really odd thing was that when we got 310 miles on a tank, which worked out to just over 24 mpg, driving to Niagara three years ago, we were cruising at mostly 75-85 mph the entire time.

26K miles on my car and i have hit the 23-24mpg 5 times now!

tire PSI should be 4-5 less then maximum. if you lower your psi, you're increasing your surface fiction on your tires.

i shift at 3-3500rpms and use cruise control as often as you can.

also if you drive with your windows/sunroof open you will get less mpg. Use your AC. No, it is not the same as having your window's open.

9K a day will keep the carbon away right? if you do it once a day in first gear, you'll still achieve 20+ mpg.

Keep it under 3? Sheesh. I have a tough time keeping it under 4, especially in first gear leaving a stop light or something. The car behind me always gets right up my ass. I shift pretty quick too. *shrug*