When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I recently concluded my long term experiment of running 91 oct (ktuned). I am now back to 87 oct due to gas price increases in CA. I will post up some fuelly numbers, soon ish.
From what Rismo stated, I too experienced a slight dip in mpg on the 1st tank of 91 oct .... go figure. after the 2nd tank and onward, it all balanced out. I personally did not see an increase nor decrease in mpg. but..... lets wait for some numbers .... stay tuned
I have a 2018 6MT Sport. Saw my best mileage ever at 48.7MPG this weekend (calculated). Flat highway driving with cruise control set to 60MPH and the tach sat just under 3K RPM. Zero traffic and weather conditions were perfect, 70 degrees, low humidity and no wind. Gas was regular Shell. I was thrilled, but no one else cared. I usually average around 36 MPG on weekdays with spirited driving back and forth to work - no highways.
I have a 2018 6MT Sport. Saw my best mileage ever at 48.7MPG this weekend (calculated). Flat highway driving with cruise control set to 60MPH and the tach sat just under 3K RPM. Zero traffic and weather conditions were perfect, 70 degrees, low humidity and no wind. Gas was regular Shell. I was thrilled, but no one else cared. I usually average around 36 MPG on weekdays with spirited driving back and forth to work - no highways.
Good for you.
As soon as the weather got warmer, my mileage shot up (CVT).
I have a 2018 6MT Sport. Saw my best mileage ever at 48.7MPG this weekend (calculated). Flat highway driving with cruise control set to 60MPH and the tach sat just under 3K RPM. Zero traffic and weather conditions were perfect, 70 degrees, low humidity and no wind. Gas was regular Shell. I was thrilled, but no one else cared. I usually average around 36 MPG on weekdays with spirited driving back and forth to work - no highways.
About a 150 mile round trip. The onboard computer showed 49.3 MPG, but my math came out to 48.7. Filled up right before and right after to do the math - same pump. Gas station and destination were literally just off the highway. For those in the NJ area it was all Turnpike and Parkway driving, so I did have to slow down to 25mpg for tolls (EzPass).
past posts have been really ... intricate, with details on every time I pump. this one will be less of that and more on my final thoughts/conclusions:
-40.2 lifetime mpg avg
-owned the car for over 14 months
-pumped 101 times
-tracked over 32k miles
-learned that 87 oct is no diff compared to 91 oct
-roof shark fins / vortex generators do nothing for/against mpg
-lighter wheels, lighter tires, not too wide of a contact patch, and higher psi help mpg's
-aftermarket intakes make for worse mpg
-exhaust seemed to have helped mpg (I think)
-ktuner had no neg impact on mpg
-pedal commander (electronic throttle controller) can REALLY have a bad impact on mpg, but boy oh boy is it fun!
-did not notice an mpg increase with wipers removed
-biggest take away = consistent/good mpg 110% depends on the drivers right foot, the path that driver chooses matters, and the owners ability to maintain the car helps
past posts have been really ... intricate, with details on every time I pump. this one will be less of that and more on my final thoughts/conclusions:
-40.2 lifetime mpg avg -owned the car for over 14 months -pumped 101 times -tracked over 32k miles -learned that 87 oct is no diff compared to 91 oct -roof shark fins / vortex generators do nothing for/against mpg -lighter wheels, lighter tires, not too wide of a contact patch, and higher psi help mpg's -aftermarket intakes make for worse mpg -exhaust seemed to have helped mpg (I think) -ktuner had no neg impact on mpg -pedal commander (electronic throttle controller) can REALLY have a bad impact on mpg, but boy oh boy is it fun! -did not notice an mpg increase with wipers removed
-biggest take away = consistent/good mpg 110% depends on the drivers right foot, the path that driver chooses matters, and the owners ability to maintain the car helps
That's been my experience as well. When I'm stomping on the gas, my MPG drops. If I take it easy while use hypermiling technique like timing lights, I've been able to get 44-47 MPG per tank on my regular commute
I have a stock airbox with a K&N drop-in and a sumole ram air scoop thing. I'm currently on stock rims with 205/50/16 and set them to 35 psi. I'm planning on lighter 15" rims like a RFP1 to see what that does to my mileage in the future. I probably won't be getting this great mileage once I move closer into the town though.
Managed to pull this off on a tank getting it up to about 8 or 9 miles to empty..... with the rv6 header, 2.25 straight through "b pipe" and the tanabe medallion axleback.... i think its pretty good.... still NO tune.....
Me being heavy footed.... as long as i keep it from 30mpg up.... i think its OK!🤪🤣😂😬
Yup, I've tried 93 for a few tanks just to see what would happen. Car did feel peppier, but gas mileage didn't have any real world improvements. Surprisingly, the first tank after I switched, the mileage was HORRIBLE. I guess the car was relearning the fuel map. After that tank, the MPG stabilized.
Looking back over my collection of thousands of pictures on my computer, I came across this one from March, 2015. I'm not sure how I achieved that, but I'm sure some coasting was involved.
I recently purchased a new 2019 Fit LX with no options including no floor mats. I'm on my third (partial) fill-up with 661 miles on the ODO and I've been amazed that I'm getting 42.4 mpg (gas receipts) with 44.6 mpg average indicated using only 87 octane all from Speedway. I'm driving 2.7% city-based miles and the balance highway miles averaging 48.2 mph with some traffic. I'm driving it very conservatively (leaving large gaps in traffic and coasting to many slow downs/stops) and not hypermiling it (I floor it on on-ramps and when I need to pass). I am quite impressed - this car is almost matching my old Honda Civic VX in gas mileage performance and is hanging in there with the Chevy Cruze MT/Diesel I was considering.
I recently purchased a new 2019 Fit LX with no options including no floor mats. I'm on my third (partial) fill-up with 661 miles on the ODO and I've been amazed that I'm getting 42.4 mpg (gas receipts) with 44.6 mpg average indicated using only 87 octane all from Speedway. I'm driving 2.7% city-based miles and the balance highway miles averaging 48.2 mph with some traffic. I'm driving it very conservatively (leaving large gaps in traffic and coasting to many slow downs/stops) and not hypermiling it (I floor it on on-ramps and when I need to pass). I am quite impressed - this car is almost matching my old Honda Civic VX in gas mileage performance and is hanging in there with the Chevy Cruze MT/Diesel I was considering.
Sounds good. Honda recommends using gas rated Top Tier. The dealer and local mechanics recommend using a tank of non-ethanol gas every few thousand miles.
Sounds good. Honda recommends using gas rated Top Tier. The dealer and local mechanics reccommend using a tank of non-ethanol gas every few thousand miles.
I find it hard to believe that one tank of gas every few thousand miles, comes to about one tank every 10 fill-up or so, is going to make any difference. The hyrgoscopic nature of ethanol causes water to accumulate in the gas tank. Is the gas tank steel or plastic? Water is heavier than gasoline. It would tend to linger at the bottom of the gas tank, no? I could be wrong but I don't think filling the tank up with pure gas is going to change that. The rubber and plastic parts that come in contact with fuel may be slightly damaged over time by both gasoline and ethanol. How much harder on them is ethanol? How much difference is one gas tank out of every 10 going to make if that one tank is 100% gasoline instead of 90%? Hard for me to imagine it is going to make much difference.
On neither web page do they recommend using non-ethanol gasoline every 10th fill-up or so. So far only your "dealer and some local mechanics" have recommended it. Honda engineers have not. While in some cases mechanics can observe things that design engineers did not get a chance to see, I don't see how that could be the case here. I'm not aware of any studies where identical cars are driven identical ways, with some using 10% ethanol all the time, and some substituting ethanol-free every now and then.
Cars designed during the last 30 years or so are all designed with 10% ethanol in mind. The metal fuel lines are designed to be a bit more corrosion resistant. The rubber or plastic fuel lines are designed not to be softened or hardened by gasoline with 10% alcohol. Actually, alcohol is probably less harmful to most elastomers and plastics than gasoline. The main problem with alcohol is it is hygroscopic, and water or water vapor corrodes steel and aluminum parts. But alcohol is not the only source of water condensation happening in gas tanks.Water from the atmosphere gets in every time you open the filler cap to put gasoline into the tank. How much more water accumulates in the tank if the fuel contains 10% alcohol? I would think probably only a tiny bit more. However the amount varies anyway – with temperature and humidity. If you want to avoid a little puddle of water at the bottom of the gas tank, the best thing to do – I think – I could be wrong – is to simply drive the car frequently, at least once a day, and to make that trip at least 10 miles. That way water from the fuel tank gets into the combustion chamber with the fuel, gets vaporized, and gets sent out the tailpipe along with the water that was produced by he combustion process. The vaporized water from the fuel tank slightly adds to the amount that travels out the exhaust valves and through the exhaust system. A small amount of water added to gasoline actually very slightly increases the amount of energy acquired from combustion of the gasoline so it will very slightly improve your fuel efficiency and horsepower – probably by a very tiny amount, an in significant amount. I'm not sure why water does this.
On neither web page do they recommend using non-ethanol gasoline every 10th fill-up or so. So far only your "dealer and some local mechanics" have recommended it. Honda engineers have not. While in some cases mechanics can observe things that design engineers did not get a chance to see, I don't see how that could be the case here. I'm not aware of any studies where identical cars are driven identical ways, with some using 10% ethanol all the time, and some substituting ethanol-free every now and then.
Cars designed during the last 30 years or so are all designed with 10% ethanol in mind. The metal fuel lines are designed to be a bit more corrosion resistant. The rubber or plastic fuel lines are designed not to be softened or hardened by gasoline with 10% alcohol. Actually, alcohol is probably less harmful to most elastomers and plastics than gasoline. The main problem with alcohol is it is hygroscopic, and water or water vapor corrodes steel and aluminum parts. But alcohol is not the only source of water condensation happening in gas tanks.Water from the atmosphere gets in every time you open the filler cap to put gasoline into the tank. How much more water accumulates in the tank if the fuel contains 10% alcohol? I would think probably only a tiny bit more. However the amount varies anyway – with temperature and humidity. If you want to avoid a little puddle of water at the bottom of the gas tank, the best thing to do – I think – I could be wrong – is to simply drive the car frequently, at least once a day, and to make that trip at least 10 miles. That way water from the fuel tank gets into the combustion chamber with the fuel, gets vaporized, and gets sent out the tailpipe along with the water that was produced by he combustion process. The vaporized water from the fuel tank slightly adds to the amount that travels out the exhaust valves and through the exhaust system. A small amount of water added to gasoline actually very slightly increases the amount of energy acquired from combustion of the gasoline so it will very slightly improve your fuel efficiency and horsepower – probably by a very tiny amount, an in significant amount. I'm not sure why water does this.
As I said, I am just passing along information. Both articles I linked point out pros and cons of using "real gas." In some cases, cars run better, and in some cases they don't. The price difference where I live is about $0.80/gal, so I don't use it very often. What the car people have told me is that is good for the fuel system in general - injectors and catalytic converter. Maybe that's just an old wive's tale.
Speaking of water in the system - a friend bought a used car, and he brought it to a mechanic for some reason. While working on it, the mechanic saw what he thought was a disconnected vacuum line, so he connected it to the carburetor. That line was for the windshield washer fluid, and the engine "burned" the washer tank dry.
The issue with quality gasoline is that much of the washing that the gas did in the intake manifold (mixes gas + incoming air --> washes over and through the intake valves and valvetrain) is moot on the GK Fit since GK engines are Gas Direct Injection (GDI) in the combustion chamber. Keeping the top surfaces of the intake valves clean is much more difficult. The only LT fix is to change your oil more often to reduce the entrained dirt concentration in circulating oil (and possibly by using a catch can).
