Fuel Mileage
01-04-2011, 05:16 PM
#29
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01-04-2011, 06:27 PM
#32
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I remember when I first got mine in '03. I tried over and over again to get good gas mileage but then I would find my foot in it again. I would be mad at myself for a second, then laugh. It takes real discipline to check and see what it can get and less to say this is my entertainment. Here is my old quote...
01-04-2011, 07:24 PM
#33
I have a 6spd auto that gets 23-27 on the highway at 70-80mph with about 2500miles a year.
I average 17 around town in light stop and go traffic with about 2000 miles a year.
That averages about 21mpg, but when I add in the 500 miles that are tracks days at 10 mpg, I average about 18mpg.
Glad you got 22 average, but that's very few miles, and I can pick 3k miles out and show 25mpg.
01-04-2011, 09:08 PM
#34
The autos get better fuel mileage, they are geared differently for highway driving.
On that note, I drive at redline, and often lol. Im sure that with a vacuum gauge and driving at 60 or 65mph we could all hit great mileage. On my way up from houston a 400 mile trip once I made 22mpg.
On that note, I drive at redline, and often lol. Im sure that with a vacuum gauge and driving at 60 or 65mph we could all hit great mileage. On my way up from houston a 400 mile trip once I made 22mpg.
01-04-2011, 10:48 PM
#35
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Let's see, you've got a 6 spd MT?
I have a 6spd auto that gets 23-27 on the highway at 70-80mph with about 2500miles a year.
I average 17 around town in light stop and go traffic with about 2000 miles a year.
That averages about 21mpg, but when I add in the 500 miles that are tracks days at 10 mpg, I average about 18mpg.
Glad you got 22 average, but that's very few miles, and I can pick 3k miles out and show 25mpg.
I have a 6spd auto that gets 23-27 on the highway at 70-80mph with about 2500miles a year.
I average 17 around town in light stop and go traffic with about 2000 miles a year.
That averages about 21mpg, but when I add in the 500 miles that are tracks days at 10 mpg, I average about 18mpg.
Glad you got 22 average, but that's very few miles, and I can pick 3k miles out and show 25mpg.
01-05-2011, 04:38 AM
#37
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Nope, there are plenty of similar reports on here, just need a healthy motor and drive it reasonably. You don't need to drive like a hypermiler to get this kind of fuel mileage. My '09 A/T commutes 56 miles daily - 10 miles town / 46 miles freeway. Usually cruise 75-80 mph on the freeway, but try to pace traffic & lights in town. Normal mileage is around 23 mpg. Lowest I've seen is 22 mpg and highest was around 25 mpg. I'm guessing I could do a bit better on weekend commutes out to the desert, but it's too hard to keep the cruising speed down. It has been very consistent over the last 25,000 miles, but has dropped slightly during the colder rainy winter, and I'm guessing it's almost time for spark plugs.
01-05-2011, 11:25 AM
#38
Pete, Your mileage is exactly what I would get under those conditions with my A/T.
I had a 73 RX3 4 spd that got 12 to 20 mpg, and had less power with gas just as high in adjusted $'s.
The high performance car that comes to mind with very high power, and good gas mileage is the Corvette.
It can run on the highway at 1500rpm, and get 25-27 mpg, but if you look on fuelly, the average is almost exactly what RX8 owners are getting.
My point is: the RX8 is a very unique GT car that has very close dimensions on the suspension with a little less weight, quieter, smoother, more agile (you can play around at the limit without spinout), and 1/3 the power.
So in effect it's the power for the mileage that we're missing, not the mileage, but we got to play for $30k instead of $50k.
I had a 73 RX3 4 spd that got 12 to 20 mpg, and had less power with gas just as high in adjusted $'s.
The high performance car that comes to mind with very high power, and good gas mileage is the Corvette.
It can run on the highway at 1500rpm, and get 25-27 mpg, but if you look on fuelly, the average is almost exactly what RX8 owners are getting.
My point is: the RX8 is a very unique GT car that has very close dimensions on the suspension with a little less weight, quieter, smoother, more agile (you can play around at the limit without spinout), and 1/3 the power.
So in effect it's the power for the mileage that we're missing, not the mileage, but we got to play for $30k instead of $50k.
01-13-2011, 10:36 AM
#39
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I drive it pretty easy, make lots of short trips in suburban traffic.
Every time somebody asks me to tell them about the RX8. I say it's 100% beautiful in every way except gas mileage, where it is just plain awful.
Every time somebody asks me to tell them about the RX8. I say it's 100% beautiful in every way except gas mileage, where it is just plain awful.
01-13-2011, 10:45 AM
#40
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Nope, there are plenty of similar reports on here, just need a healthy motor and drive it reasonably. You don't need to drive like a hypermiler to get this kind of fuel mileage. My '09 A/T commutes 56 miles daily - 10 miles town / 46 miles freeway. Usually cruise 75-80 mph on the freeway, but try to pace traffic & lights in town. Normal mileage is around 23 mpg. Lowest I've seen is 22 mpg and highest was around 25 mpg. I'm guessing I could do a bit better on weekend commutes out to the desert, but it's too hard to keep the cruising speed down. It has been very consistent over the last 25,000 miles, but has dropped slightly during the colder rainy winter, and I'm guessing it's almost time for spark plugs.
01-13-2011, 01:16 PM
#43
I changed my measurement to be "faulty", as in US MPG instead of my usual metric to provide you with that info 
The best MPG is from a long trip with spirited mountain driving, but not that often over 60mph. So both up and downhill, hehe.
The best MPG is from a long trip with spirited mountain driving, but not that often over 60mph. So both up and downhill, hehe.
01-13-2011, 08:05 PM
#44
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If we made 2 graphs, one with average moving speed vs mpg, and another with commute distance vs mpg, there would be a curve that makes sense. One could predict with some accuracy exactly where their mpg would be, based on their commute distance, and their average moving speed on the other.
That gives me some idea of how people can punch above 20 mpg. One must have a commute of greater than 25 miles one-way, have a balance of 3/4 freeway to 1/4 town, travel at faster freeway speeds of 75 mph, and have an AT. Those are quite a few conditions however.
Although I haven't driven enough to fill up Fuelly since the rx8 engine replacement, the fact that my mileage is sucky no matter what car means this wide varyance can happen with any vehicle based on the commute condition. Fact is, my commute takes 25-30 minutes for only 9 miles the short way, or 15 miles the long way. Split 50/50 between freeway and town. My gps says my average speed is 19 mph, my moving average speed is 25 mph, my moving time is 20 minutes, my stopped time is 6 minutes. Stop and go is a daily thing that goes on for several miles.
Under the above scenario, my rx8 got 14mpg on the low end if I floored it on every single acceleration, or 16.5mpg if I lugged around in 5th gear in 25mph zones. From one extreme to the other, not much difference in mpg. I simply don't have a long enough commute, or enough freeway miles, to reach higher mpg numbers.
Somewhere in between is where many would fall, 17-19mpg depending on MT or AT.
My theory is, this has nothing to do with "hand-built" engine tolerance. I can actually look at someone's reported mpg figure and know exactly the type of frustrating commute creates 14mpg, and what smooth sailing commutes people at 20mpg have, and the in-between folks at 18mpg. Not hard to understand, no magic involved.
Although I haven't driven enough to fill up Fuelly since the rx8 engine replacement, the fact that my mileage is sucky no matter what car means this wide varyance can happen with any vehicle based on the commute condition. Fact is, my commute takes 25-30 minutes for only 9 miles the short way, or 15 miles the long way. Split 50/50 between freeway and town. My gps says my average speed is 19 mph, my moving average speed is 25 mph, my moving time is 20 minutes, my stopped time is 6 minutes. Stop and go is a daily thing that goes on for several miles.
Under the above scenario, my rx8 got 14mpg on the low end if I floored it on every single acceleration, or 16.5mpg if I lugged around in 5th gear in 25mph zones. From one extreme to the other, not much difference in mpg. I simply don't have a long enough commute, or enough freeway miles, to reach higher mpg numbers.
Somewhere in between is where many would fall, 17-19mpg depending on MT or AT.
My theory is, this has nothing to do with "hand-built" engine tolerance. I can actually look at someone's reported mpg figure and know exactly the type of frustrating commute creates 14mpg, and what smooth sailing commutes people at 20mpg have, and the in-between folks at 18mpg. Not hard to understand, no magic involved.
Last edited by User24; 01-13-2011 at 08:12 PM.
01-13-2011, 08:12 PM
#45
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My "commute" to school is around 18 miles.
about a mile at 25mph to get out of my neighborhood
5-6 miles on a 2 lane road that varies from 45-55
10 miles interstate (i go around 70-75)
then 2 miles with 5 or 6 lights to go through.
I easily get over 20 (with a manual) with the majority of my driving being that.
about a mile at 25mph to get out of my neighborhood
5-6 miles on a 2 lane road that varies from 45-55
10 miles interstate (i go around 70-75)
then 2 miles with 5 or 6 lights to go through.
I easily get over 20 (with a manual) with the majority of my driving being that.
01-13-2011, 08:48 PM
#48
Paimon I actually sent it as a request weeks ago with a positive reponse, but if everyone emailed them they might speed up the process. The email said they don't do one of everyone because it would envoke cheating, but they believe if its just between friends that it could be more honost. But you all should email them and suggest it just for fun :P
01-13-2011, 11:08 PM
#50
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My 8 is almost 7 year old and on it's third engine in 120,000 miles. I realize every 8 is different but.........
My parents live 170 miles up I-35 (not many hills, pretty straight shot, toll way for a good distance of the drive) and the best I have ever gotten was the 20MPG I got recently. I rarely hit close to 20MPG even when I was bone stock let alone average it. I'm a big cruise control guy and on the toll way there is no traffic so I set it and forget it (lots of cops and I am paranoid they will mail me a ticket because of the camera system
)
I have done that drive probably 50 times in my 8 and there have been times late at night or early morning that I have literally hit no traffic and cruised 70-75MPH the whole way and still only got close to 20MPG.
Before I started using Fuelly, I logged every tank on a spreadsheet and I can look back and honestly through mods (BHR fuel pump, Nitrous, exhaust, etc., etc.), changes in driving habits (from 70 miles a day all highway to less than 4 miles a day), different engines, premix, no premix, etc. It has stayed pretty much the same and is on par with what stock 8's are getting.
My buddy tracks his R3 on Fuelly and we get almost the same exact mileage and his car is brand new. My other buddy who has an 8 tracks his mileage and it is pretty on par with mine even though I have three times the mileage he does. All of the SARX members have pretty much the same mileage. When we do the Statewide meet we all fuel up together (20+ cars) and those that started with full tanks in our faster group are pretty much all at the same fuel level half way through the run. I do notice a huge drop in mileage during those runs but then again we are at or near redline for miles upon miles.
My parents live 170 miles up I-35 (not many hills, pretty straight shot, toll way for a good distance of the drive) and the best I have ever gotten was the 20MPG I got recently. I rarely hit close to 20MPG even when I was bone stock let alone average it. I'm a big cruise control guy and on the toll way there is no traffic so I set it and forget it (lots of cops and I am paranoid they will mail me a ticket because of the camera system
)I have done that drive probably 50 times in my 8 and there have been times late at night or early morning that I have literally hit no traffic and cruised 70-75MPH the whole way and still only got close to 20MPG.
Before I started using Fuelly, I logged every tank on a spreadsheet and I can look back and honestly through mods (BHR fuel pump, Nitrous, exhaust, etc., etc.), changes in driving habits (from 70 miles a day all highway to less than 4 miles a day), different engines, premix, no premix, etc. It has stayed pretty much the same and is on par with what stock 8's are getting.
My buddy tracks his R3 on Fuelly and we get almost the same exact mileage and his car is brand new. My other buddy who has an 8 tracks his mileage and it is pretty on par with mine even though I have three times the mileage he does. All of the SARX members have pretty much the same mileage. When we do the Statewide meet we all fuel up together (20+ cars) and those that started with full tanks in our faster group are pretty much all at the same fuel level half way through the run. I do notice a huge drop in mileage during those runs but then again we are at or near redline for miles upon miles.
Last edited by 9krpmrx8; 01-13-2011 at 11:15 PM.