30.3 mpg!!!
09-07-2009, 12:39 PM
#26
It's possible. I got mid 20s consistently with my car during a 2700 mile road trip from Florida to Tennessee to North Carolina and back to Florida. Most of the tanks were highway-only, and I would get between 24-26 mpg on those. If I drove more conservatively I would bet I would have gotten high 20's, but it's too tempting to step on the gas (especially with a supercharger).
09-07-2009, 01:01 PM
#27
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been reading this thread and can say that it might be possible but, there have to be conditions that took place to be possible.
If you take back roads and it is very hilly and the speed limit is very low, say 35 or so, it is possible if you have a stickshift. As long as the grade is not so much so that you cannot maintain speed, you can put the 8 in 6th, and go up and down (more down) the mountains just north of atlanta such as the case with hwy 19 or 41, sorry been a while since I have been up that way, believe it is 19. Anyway, as you go up the mountain, the rpms are so low that even at a good load on the engine, you are not using that much fuel as you dont have much available power at low rpms (see your dyno for those of us without FI) As you decend the mountain and wind down it slowly and enjoy the turns while you are at it,
, your mpg will be sky high as long as you dont hit the clutch and do all engine braking.
I went to NC and when I came back, I took my time to see just how good my mpg would be if i drove very conservatively. I am not sure about the rest of you but, I got just over 200 miles on HALF of a tank, respectively. Take into consideration that it holds about 16 gallons when completely empty and in my case, I have over a half tank of gas even when it says I have just a half tank (yes I have measured it cause I wondered why I could only get 6.5 gallons in when I have hit just under a half tank before many times) I actually got about 30mpg myself but, I dont normally drive that way and usually get about 20 with mixed driving just like most everyone else. I am saying it is possible but, certain circumstances have to be in play to do so. The auto version with the taller final gear is capable of it but, again, under certain circumstances. I, personally, would prefer mazda to keep the gearing short except for 6th gear which should be made much taller and let the driver decide when and where to use it. Thank the car magazines for keeping stickshift drivers lazy with the 30-50 and 50-70 passing performance catagory. If I want to get up and go, drop the clutch, find a gear I like and go.
If you take back roads and it is very hilly and the speed limit is very low, say 35 or so, it is possible if you have a stickshift. As long as the grade is not so much so that you cannot maintain speed, you can put the 8 in 6th, and go up and down (more down) the mountains just north of atlanta such as the case with hwy 19 or 41, sorry been a while since I have been up that way, believe it is 19. Anyway, as you go up the mountain, the rpms are so low that even at a good load on the engine, you are not using that much fuel as you dont have much available power at low rpms (see your dyno for those of us without FI) As you decend the mountain and wind down it slowly and enjoy the turns while you are at it,
, your mpg will be sky high as long as you dont hit the clutch and do all engine braking. I went to NC and when I came back, I took my time to see just how good my mpg would be if i drove very conservatively. I am not sure about the rest of you but, I got just over 200 miles on HALF of a tank, respectively. Take into consideration that it holds about 16 gallons when completely empty and in my case, I have over a half tank of gas even when it says I have just a half tank (yes I have measured it cause I wondered why I could only get 6.5 gallons in when I have hit just under a half tank before many times) I actually got about 30mpg myself but, I dont normally drive that way and usually get about 20 with mixed driving just like most everyone else. I am saying it is possible but, certain circumstances have to be in play to do so. The auto version with the taller final gear is capable of it but, again, under certain circumstances. I, personally, would prefer mazda to keep the gearing short except for 6th gear which should be made much taller and let the driver decide when and where to use it. Thank the car magazines for keeping stickshift drivers lazy with the 30-50 and 50-70 passing performance catagory. If I want to get up and go, drop the clutch, find a gear I like and go.
Last edited by cliffkemp; 09-07-2009 at 01:03 PM. Reason: spelling
09-07-2009, 02:18 PM
#28
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Maybe....wait no i dont mess up on math. My A's in math in all of my college courses tell me different, but for real i got 30.3. I know it was a fluke and it will never happen again, well atleast i think it wont, but i would not mind if it did ha ha
Also i did take backroads. I took 411 most the way there instead of 75. Its all mostly a two way road. I had my brother with me and my Girlfriend. And i did not drive they way i normally do bc i went to atlanta for a braves game and wanted to save more money by driving more conservative. I also did not hit any traffic in atlanta since i got there early. Which helped tremendously.
Also i did take backroads. I took 411 most the way there instead of 75. Its all mostly a two way road. I had my brother with me and my Girlfriend. And i did not drive they way i normally do bc i went to atlanta for a braves game and wanted to save more money by driving more conservative. I also did not hit any traffic in atlanta since i got there early. Which helped tremendously.
09-10-2009, 11:35 AM
#30
Power!!
Keep posting up more of your next average mpgs from your next couple of tanks so we can see where you are normally. At the very least you are getting some of the best MPG of all RX8s out there even at mid-20's.
09-10-2009, 01:41 PM
#31
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Sure you can. Sixth gear on a secondary highway nonstop at 50 mph on cruise control will probably net you around 30 mpg. But no stock RX-8 has ever broken 30mph cruising at 80 mph for 300 miles unless it had a heck of a tailwind or was drafting.
09-10-2009, 01:48 PM
#32
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I just drove to/from atlanta this weekend, I got right around 20 mpg's on the highway...
Got slightly over 20 on the way down there, and filled up yesterday before the way home, am currently sitting at 287 miles with the gas light on, so right around 20 mpg's...
I find 30+ hard to believe. I was going roughly 80 mph the whole way on the highway, with a few stops, and maybe one to three cases of vigorous passing of slow cars...
Got slightly over 20 on the way down there, and filled up yesterday before the way home, am currently sitting at 287 miles with the gas light on, so right around 20 mpg's...
I find 30+ hard to believe. I was going roughly 80 mph the whole way on the highway, with a few stops, and maybe one to three cases of vigorous passing of slow cars...
09-10-2009, 01:51 PM
#33
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It is possible, but that would be a DAMN long trip... Hell, it took me 5 hours traveling at 80 mph. Engine turning right around 4k rpm, I suppose slowing it down to about 70 or below may have helped, but my guess would be only marginally.
09-10-2009, 02:29 PM
#37
1st =10mph
2nd=20mph
3rd=30mph
etc..
Whenever you hit 10, switch to 2nd, when you hit 20 shift to 3rd... just the way I do it. This puts me around 3krpm max for each shift. This method nets me around 21mpg mixed driving
09-10-2009, 05:39 PM
#38
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Wish I had my camera with me. I went to fill up today at walmart here in Carrollton Ga and, the fuel gauge was pointing on the second line below the half tank mark. I put in, with my oldest daughter present, 7.87 gallons of gas. As stated before when I went from North Carolina back to Ga and went up and down the mountains on the back roads, I got 200 miles on a half tank of gas.
When my car hits right at a half tank with the needle, I am doing good to put 6.5 gallons of gas in it and that is after the pump cuts off a few times and it tries to splash out cause the pump cuts off late (I hate that). It put me at 30 mpg too. I averaged about 45mph or so but kept it in 6th gear as much as possible above 20 or so mph. There were few places I had to stop for lights and all. I had filled up and drove about 20 miles in the local town in NC. I drove home and wish I could have taken pictures for you all to see the 200 miles with a half tank showing. If I think about it, next time, I will take a picture before and after a fill up at about half a tank. I will include the main odometer so that there are no allegations of false info.
I still stand firm on the gearing issue. I understand the A/F meter rebuttal and, it is useful but, it just tells mixture content. Again, there is a fine line here but, the number of times an injector fires is based on rpms and the amount is what the A/F is picking up. All I can tell you is that I went up and down the mountains on the way home in 5th and 6th gear only (except if I had to stop) I kept the rpms at around 2k unless the speed limit was over 40 then was 6th gear only. I even set my cruise at 38 unless I could not take the turn safely. Just telling you all my experience as well. I hope mazda changes the ratio for 6th to have better mileage and be closer to 25mph/1000 rpms, instead of about 20.
By the way, I am not saying the A/F meter is wrong or anything of the sort. I am saying it is another tool to use to help determine the best way to drive your car and get the most out of it whether mpg, or tuning. Please do not take offense to anything I say. It is not a right or wrong kind of statement. I am just giving information and others can chose to use it or not.
When my car hits right at a half tank with the needle, I am doing good to put 6.5 gallons of gas in it and that is after the pump cuts off a few times and it tries to splash out cause the pump cuts off late (I hate that). It put me at 30 mpg too. I averaged about 45mph or so but kept it in 6th gear as much as possible above 20 or so mph. There were few places I had to stop for lights and all. I had filled up and drove about 20 miles in the local town in NC. I drove home and wish I could have taken pictures for you all to see the 200 miles with a half tank showing. If I think about it, next time, I will take a picture before and after a fill up at about half a tank. I will include the main odometer so that there are no allegations of false info.
I still stand firm on the gearing issue. I understand the A/F meter rebuttal and, it is useful but, it just tells mixture content. Again, there is a fine line here but, the number of times an injector fires is based on rpms and the amount is what the A/F is picking up. All I can tell you is that I went up and down the mountains on the way home in 5th and 6th gear only (except if I had to stop) I kept the rpms at around 2k unless the speed limit was over 40 then was 6th gear only. I even set my cruise at 38 unless I could not take the turn safely. Just telling you all my experience as well. I hope mazda changes the ratio for 6th to have better mileage and be closer to 25mph/1000 rpms, instead of about 20.
By the way, I am not saying the A/F meter is wrong or anything of the sort. I am saying it is another tool to use to help determine the best way to drive your car and get the most out of it whether mpg, or tuning. Please do not take offense to anything I say. It is not a right or wrong kind of statement. I am just giving information and others can chose to use it or not.
Last edited by cliffkemp; 09-10-2009 at 05:43 PM. Reason: other info
09-10-2009, 10:52 PM
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I did a majority of mine going no more than 45 meaning I kept the rpms below 2250 for most of the time going up and down the mountains of north Ga on US 19. I kept the car in 6th gear and did mainly engine braking going down and put the cruise on 38 going up as the limit was 35. These were unique circumstances in which low rpms and a good bit of engine braking along with low hwy speed (never went about 55) played a huge factor. When I got on the interstate in atlanta on 400, 285, and then i20, and went at the usual 65 to 75, i went through gas as usual and got about 350 miles on that tank in all. Normally on all highway driving, I get 22 to 24 at best. I am saying it is possible but, not the norm that is for sure.
09-10-2009, 11:33 PM
#41
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Ok i just filled up with city and highway miles. Mostly city with traffic at UT and got 22. Isnt to bad for mostly city. I wish it was as high as the 30.3 lol, but thats still really good.
09-12-2009, 07:38 AM
#44
GoSpoddyGo!!!
Hi
Well I live in Northern Ireland I drive 30 miles to work and 30 back.
I do 80/20% motorway/city driving, there is also a 50mph motorway restriction for a number of miles at the moment.
The highest average I get is about 26mpg according to my scan gauge II.
The interesting thing is when I glance at the reading I can get 30 plus mpg on the motorway, now depending if the stretch of motorway is level I get 31-33mpg, this is driving at anthing between 57-65mph. 70mph will go down to 27-29mpg on the scan gauge.
However there are naturally parts of the road where you are going up a gradient and down, and when going up the mpg will drop to 18mpg up to 25mpg.
The best return I got was out of manual or stick shift gear, in neutral, going down a steepish hill on the motorway coasting at 50mph in the motorway restriction area, I got 153mpg lol.
Now whats all this talk about 30.3mpg lol wish I could have taken a photo was a great sight if only for 10 secs until the road was level again lol.
Basically if you keep in top gear drive along at 50-55mph and are on a flat level road at constant speed, dare I say it even drive behind a truck that will act as a wind breaker you can achieve high mpg.
I don't have cruise control on my 2004 rx8, its a 6 speed, so I always drive in top gear as soon as possible. I drive in 30mph zones in 5th which keeps the revs down and mpg up according to the scan gauge. I switch to 6th when doing 40mph and above.
Now the thing about the rotary at constant low rpm gear changes and 45mph etc is you will need to redline the car a few times when on a back road to help blow out the carbon. I have noticed the car can drive worse if you don't do this and actually it helps keep you in the 29mpg plus when you are driving on the longer roads, your normal driving.
But on average I get between 24-26mpg, so aveaging 30mpg does seem a dream, but it was probably liked you said constant speed, very small start/stop sessions and less city traffic.
It was interesting to hear about your passengers and luggage though, ie extra weight would imply more fuel consumption. Maybe you would have gotten 35-40mpg
if you had kicked them out lol.
But well done, my milage just passed 74k and she is getting more fuel efficient each day.
Well I live in Northern Ireland I drive 30 miles to work and 30 back.
I do 80/20% motorway/city driving, there is also a 50mph motorway restriction for a number of miles at the moment.
The highest average I get is about 26mpg according to my scan gauge II.
The interesting thing is when I glance at the reading I can get 30 plus mpg on the motorway, now depending if the stretch of motorway is level I get 31-33mpg, this is driving at anthing between 57-65mph. 70mph will go down to 27-29mpg on the scan gauge.
However there are naturally parts of the road where you are going up a gradient and down, and when going up the mpg will drop to 18mpg up to 25mpg.
The best return I got was out of manual or stick shift gear, in neutral, going down a steepish hill on the motorway coasting at 50mph in the motorway restriction area, I got 153mpg lol.
Now whats all this talk about 30.3mpg lol
wish I could have taken a photo was a great sight if only for 10 secs until the road was level again lol.Basically if you keep in top gear drive along at 50-55mph and are on a flat level road at constant speed, dare I say it even drive behind a truck that will act as a wind breaker you can achieve high mpg.
I don't have cruise control on my 2004 rx8, its a 6 speed, so I always drive in top gear as soon as possible. I drive in 30mph zones in 5th which keeps the revs down and mpg up according to the scan gauge. I switch to 6th when doing 40mph and above.
Now the thing about the rotary at constant low rpm gear changes and 45mph etc is you will need to redline the car a few times when on a back road to help blow out the carbon. I have noticed the car can drive worse if you don't do this and actually it helps keep you in the 29mpg plus when you are driving on the longer roads, your normal driving.
But on average I get between 24-26mpg, so aveaging 30mpg does seem a dream, but it was probably liked you said constant speed, very small start/stop sessions and less city traffic.
It was interesting to hear about your passengers and luggage though, ie extra weight would imply more fuel consumption. Maybe you would have gotten 35-40mpg
if you had kicked them out lol.But well done, my milage just passed 74k and she is getting more fuel efficient each day.
Last edited by spoddyandthemazda; 09-12-2009 at 07:40 AM.
09-15-2009, 04:18 PM
#45
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Dude are you sure you don't have a fuel leak? Have you driven around with someone that has a manual 8 before since you are new to it? Maybe you are just staying in 1,2,3 gears way too long. When I drive 'normal' I go through the gears as a multiple of 10 of the gear you're in.
1st =10mph
2nd=20mph
3rd=30mph
etc..
Whenever you hit 10, switch to 2nd, when you hit 20 shift to 3rd... just the way I do it. This puts me around 3krpm max for each shift. This method nets me around 21mpg mixed driving
1st =10mph
2nd=20mph
3rd=30mph
etc..
Whenever you hit 10, switch to 2nd, when you hit 20 shift to 3rd... just the way I do it. This puts me around 3krpm max for each shift. This method nets me around 21mpg mixed driving
09-16-2009, 08:53 AM
#48
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Getting around 12mpg... all city driving and i'm driving the car as intended =)
Last edited by mat128; 09-16-2009 at 09:38 AM. Reason: just read the MNAO warranty thread :(
