Howdy, Stranger!

It looks like you're new here. If you want to get involved, click one of these buttons!





Mazda RX-8 Gas Mileage Reports

245

Comments

  • trispectrispec Posts: 305
    I have a 40 mile round trip stop and go heavy traffic commute in Boston with no highway time.

    After 3500 miles with my RX-8 AT using full auto, no paddle shifting, no fast take offs, and staying under the speed limit, I pulled 17mpg. Full auto constantly shifts to the minimum speeds for 2nd, 3rd and 4th and drops rpm to 1500 or less for maximizing coasting. You end up riding the brake a lot more since there is little engine breaking available in 2nd, 3rd and 4th at low rpm levels. But driving like that all the time would be a horrible waste of the RX-8 resources and probably would cause carbon build up in the engine systems along with extra brake wear.

    Driving with paddle shifting between 2500 and 4000 rpm strictly, I get 15mpg. This is the best balance of enjoying the RX-8 resources and traffic reality during the day.

    Driving with paddle shifting between 4000 and 6000 rpm strictly I get 11 mpg. :) This is hard to do on a practical level in the city. Late nights is the only possible time and even then traffic can get in the way.
  • trispectrispec Posts: 305
    Did a small trip today, mostly highway. Got 22.3 mpg. Used full auto, no paddles. Had some nice long stretches at 80+ mph going north on I93 Boston to Franklin above Concord, then across on 11a and 11 to 16 and then down I95.

    I'm very happy with that.
  • ukjimukjim Posts: 63
    2004, MT with 14,200 M on the clock. Took weekend trip to Palm Springs from LA.
    One passenger, trunk full but back seats empty.

    Outbound: 168.2 miles at average speed of 29.5 MPH (2 hours plus in stop/go 1st gear traffic due to overturned truck on 10 FWY :mad:) 17.84 MPG

    Return: 136.7 miles at average speed of 63.5 MPH (steady 75 -83 mph on 60 FWY :blush: ) 20.12 MPH
  • I've been keeping track of gas mileage since day one, which is over 2 yrs ago.

    miles: 26275.7
    gallons: 1398.596
    miles/gallon: 18.79
    price: $2847.39
    price/gallon: $2.036
    miles/dollar: 9.23
    miles/day: 30.62
    octane: mostly 89

    The normal mpg range is 17-22. The 3 exceptions were when I took the car to Sebring Racetrack where it average 8-9 mpg. Fun, fun, fun!
  • dwynnedwynne Posts: 4,018
    Filled up yesterday and got my best mileage so far. Around 1,800 miles on the car now (6mt) and got about 16.25 mpg. This is the best I have gotten for just commuting

    Well, the next tank is back down to 14.5 mpg for the same commute, so getting over 16 mpg was just a temporary thing :(

    Dennis
  • lr3rx8lr3rx8 Posts: 7
    2004 RX-8 33500 miles bought new Nov 2005 for a real good price.

    Worst mileage 14.8 Georgia mountain autocross
    Best 22.8 hwy - 74 mph (wife driving)
    Daily driving 16-17 45 mile round trip commute. Drive easy 17.7 maybe, Drive hard 16.0 - I pick drive hard...

    BTW first set of tires lasted 30K now have Dunlops - much quieter, better ride, slightly better mileage.
  • stbartonstbarton Posts: 1
    Would I be harming the RX8 engine if I used regular 87 octane gas? Also would that effect my gas mileage negatively?
  • trispectrispec Posts: 305
    I put 89 octane Shell gas into my RX-8 AT that was 20% full with the Shell 93 Octane. My MPG jumped from the normal 14.5 MPG to 16 MPG pure city driving. I'm going to continue mixing back and forth, 93 octane to 89 octane, to see if the MPG correlates consistently. Pathstar said it might happen, but I wasn't thinking it could be that dramatic of a difference in MPG. I tried the 87 octane once, and there was no difference.
  • carfanatic007carfanatic007 Posts: 267
    I could never justify buying such a small car, that isn't as fast as the competition that gets such lousy gas mileage. The 350Z gets about 25 MPG. Even the Mustang GT gets better mileage and it is a V8! I owned a 1973 Mazda RX2. Fast little bugger, but it had oil burning problems. I wish they could work out the kinks in the Rotary engine. Seems like they haven't yet.
  • trispectrispec Posts: 305
    There are not really any "kinks" in the rotary engine. Rotary's are designed to burn oil. Point of the rotary design has little to do with MPG. If high MPG is the goal, then buy a Hybrid that only a NASA scientist can fix.

    The following are the points to the rotary engine design:

    1) Simple design engine design with few moving parts raises overall reliability over time. A design life of 200K miles on the old rotary designs, a sports car engine, was unheard of in the complicated multi-value piston world of the past. The Renesis Rotary's design life is 500K miles. Racing a rotary engines means one re-build per season, where as racing a piston engines means re-builds after every race.

    2) Much lower torque at low RPMs is a wear and tear saver on the entire drivetrain.

    3) The drag racing mentality of torque heavy engine design, based on a NASCAR formula in the USA is just dumb. Go watch any VOD Car video as torque heavy monster cars drag off screeching burn tires, only to crash half a block down the road as they simply loose control of the poorly torque balanced car.

    4) Engine weight and size eliminate frontend steer compared to the high center of gravity weight of any piston designed engines. Acions might go to the flat four and flat six piston designs of Porche and Subaru.
  • trispectrispec Posts: 305
    There are not really any "kinks" in the rotary engine. Rotary's are designed to burn oil. Point of the rotary design has little to do with MPG. If high MPG is the goal, then buy a Hybrid that only a NASA scientist can fix.

    The following are the points to the rotary engine design:

    1) Simple design engine design with few moving parts raises overall reliability over time. A design life of 200K miles on the old rotary designs, a sports car engine, was unheard of in the complicated multi-value piston world of the past. The Renesis Rotary's design life is 500K miles. Racing a rotary engines means one re-build per season, where as racing a piston engines means re-builds after every race.

    2) Much lower torque at low RPMs is a wear and tear saver on the entire drivetrain.

    3) The drag racing mentality of torque heavy engine design, based on a NASCAR formula in the USA is just dumb. Go watch any VOD Car video as torque heavy monster cars drag off screeching burn tires, only to crash half a block down the road as they simply loose control of the poorly torque balanced car.

    4) Engine weight and size eliminate frontend steer compared to the high center of gravity weight of any piston designed engines. Exceptions might go to the flat four and flat six piston designs of Porsche and Subaru.
  • mstricklermstrickler Posts: 1
    About half of the AT's revs/hp deficit was eliminated for 2006. The old Mazda 4-speed forced the drastic cutback in engine speed and output.
    Mitch
  • trispectrispec Posts: 305
    The 2004-5 RX-8 AT only has 4 ports for intake rather than the 6 ports on the MT. Also, 1st gear on the 4sp AT matches 2nd gear on the MT. The 2006 RX-8 AT 6sp has 6 ports, but the AT tranny still can't handle 9000 RPM, so rev/hp are limited at 7500 RPM.
  • paul_in_dcpaul_in_dc Posts: 6
    '05 RX-8, bought in Dec '04

    17 around town
    23 highway
    11 track

    My worst "around town" mpg was 15, but that was mostly due to a heavy foot and high revs. :blush:

    Why do people b*tch about the mileage? This is a sports car, not an econ-o-box. Our mileage is similar to other comparable sports cars.
  • from_flfrom_fl Posts: 113
    RX-8 is a sports GT(4 seats).
    It is not a true sports car. RX-7 was a sports car.
    I like RX-8 but couldn't get over its poor MPG issue.
    Mazda has this engine for at least 10 years but yet they still couldn't improve its fuel consumption and motor oil issue. My IS250 can go 400 miles(75% freeway) per tank at 29/30+ MPG. Expect more from your sporty car.
  • from_flfrom_fl Posts: 113
    Correction..

    Mazda has this engine for at least 20 years but yet ..
  • trispectrispec Posts: 305
    When there's no more gas, the rotary engine be the only non-electric engine running and it'll be burning hydrogen. Piston's will go the way of steam engines.
  • paul_in_dcpaul_in_dc Posts: 6
    Not a sports car? Ever seen one on the track? Check out the Grand Am series. :D :D :D
  • paul_in_dcpaul_in_dc Posts: 6
    Where in the world do you get 20 years? The Renesis is only a couple years old. Ford has been making piston engines for almost 100 years, yet the Mustang gets worse gas mileage than the RX-8. What's their excuse? :lemon:
Sign In or Register to comment.