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I did a 360 mile trip this weekend, mostly highway, some stop and go. MPG meter on the dash said I got 29.9 mpg. Even got it over 30 once or twice. But I do drive like an old man....well because I am.
 

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Regarding a 4-gallon reserve, that seems awfully high. Regarding running it almost to empty, are you looking at the fuel gauge or the miles to empty estimate? These days it seems when the dummy light comes on you can easily do another 50 miles.
Agreed. The DTE (distance to empty) is a calculation based on recent mileage so it can be misleading. For example if you are sitting in traffic getting 0 MPG the DTE will drop like a rock. My other vehicles have about 2 gallons remaining once they hit empty and the low fuel light will come on with about 45 miles of range left.
 

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Agreed. The DTE (distance to empty) is a calculation based on recent mileage so it can be misleading. For example if you are sitting in traffic getting 0 MPG the DTE will drop like a rock. My other vehicles have about 2 gallons remaining once they hit empty and the low fuel light will come on with about 45 miles of range left.
Identifying the gallons remaining once you hit empty or get a fuel level warning light for the Santa Cruz will be helpful for all to know. Hopefully someone can ID that for us all.
 

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Just hit 1100 miles in my SC (Limited with the Turbo). Just completed a trip to Sedona, approximately 220 miles round trip with 5k+ elevation gain there and 5k+ elevation drop on the way back. Averaged 24 MPG on the way up and 31.4 MPG on the way back. That amounts to 27.7 MPG for the whole trip. Also, this was with a mountain bike in the bed hanging over the tailgate and speeding uphill at 75-80 MPH at times.
 

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Just hit 1100 miles in my SC. Just completed a trip to Sedona, approximately 220 miles round trip with 5k+ elevation gain there and 5k+ elevation drop on the way back. Averaged 24 MPG on the way up and 31.4 MPG on the way back. That amounts to 27.7 MPG for the whole trip.
BTW, for Americans, may wish to mention if your MPG are naturally aspirated or turbo engine.
 

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It seems like my latest full tank of gas is lasting forever now that I'm home and just doing normal daily things with my SC. I have yet to see another SC on the road. Today I even drove right by the Hyundai North American headquarter and not one SC in the parking lot out front. I thought for sure I'd see a few there that employees bought through their inside track. I saw lots of Limited's being shipped there on the Chuck & Casey lists. MPG's are looking good IMHO for what this vehicle is capable of.
 

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Identifying the gallons remaining once you hit empty or get a fuel level warning light for the Santa Cruz will be helpful for all to know. Hopefully someone can ID that for us all.
Filled up as soon as low fuel light came on. 14 1/2 gallons. That means there is a 3 gallon reserve.
 

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Has anyone here filled up there tank when “distance to empty” read zero (0) - I’m curious, I typically do this to all my vehicles to see how much is left in the tank…
 

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I don't have the luxury of pushing it that far ... my commute is 97km each way with no gas stations in between. LOL But I can solidly get over 600km with over 100km DTE showing on the display. At least in my highway driving. I did just shy of 500km on tonight's fill, from 1/4 tank (25% in Bluelink) 495.7km on 45.81L - which included my 2+ hour offroad adventure last week, so I expected worse than 9.2L/100km. So far my measured mileage is consistently better than what the computer is reporting. So I'm taking the dashboard numbers with a grain of salt.
 

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I don't have the luxury of pushing it that far ... my commute is 97km each way with no gas stations in between. LOL ...
Don't you want to take one for the team? ...in the interest of science?
Wait... don't they have 5-gal gas cans in Canada?

.... So far my measured mileage is consistently better than what the computer is reporting....
Someone also reported that their speed was reading 2 mph low, which agrees with your observation about the distance error.
 

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Don't you want to take one for the team? ...in the interest of science?
Wait... don't they have 5-gal gas cans in Canada?


Someone also reported that their speed was reading 2 mph low, which agrees with your observation about the distance error.
Probably not, hosers are metric. Kidding aside, speedos arent off by a certain mph, its a percentage off. So it may read 2mph off at 75mph but not necessarily at 25mph. Its pretty common and I usually compensate with tire size when its time.
 

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Don't you want to take one for the team? ...in the interest of science?
Wait... don't they have 5-gal gas cans in Canada?
Someone also reported that their speed was reading 2 mph low, which agrees with your observation about the distance error.
But I don't want to carry a gas can around. I also travel through a giant cellular dead zone, so I can't call any roadside assistance to bail me out. LOL

I'll have to do a GPS reading of the speed and see if there's something out of whack there. I did briefly touch on 8.7L/100km this morning arriving at work ... 0.1 better than the EPA rating!
 

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Octane will most def affect your MPG and your HP in high compression motors, and forced induction motors. How do you know if you need high octane? Well, your car will state what fuel it requires, usually in the fuel refill area, fuel up with what octane it says.

Running a lesser fuel than the car asks for will not hurt the car since there are built-in safeties, but this is where you start losing MPG and HP. The timing is reverted when it detects knock on lower octane, since lower octane has a lower detonation point, which the reverted timing results in lesser fuel economy and performance. Higher octane fuel has a higher detonation point, and without the knock sensor detecting knock, the computer will advance the timing allowing better performance and better fuel economy as it is now running leaner. The leaner you can run, the more power and more fuel-efficient a car is. The computer will run it as lean as it can without causing detonation (knock), so the higher the octane, the leaner it can run before it hits detonation, which equals more power and better fuel economy.

With all that being said, there are 2 rules of thumb. Always run high octane on forced inducted cars (they almost all require it) and don't waste money putting high octane in cars that do not state that they require it, that is just throwing money away with zero benefit.

I think it was popular mechanics years ago that did the math showing that the lower cost of 87 at the pump actually cost more than premium due to the loss of mileage on cars requiring high octane.
 

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Octane will most def affect your MPG and your HP in high compression motors, and forced induction motors. How do you know if you need high octane? Well, your car will state what fuel it requires, usually in the fuel refill area, fuel up with what octane it says.

Running a lesser fuel than the car asks for will not hurt the car since there are built-in safeties, but this is where you start losing MPG and HP. The timing is reverted when it detects knock on lower octane, since lower octane has a lower detonation point, which the reverted timing results in lesser fuel economy and performance. Higher octane fuel has a higher detonation point, and without the knock sensor detecting knock, the computer will adjust the timing to run more aggressively allowing better performance and better fuel economy as it is now running leaner. The leaner you can run, the more power and more fuel-efficient a car is. The computer will run it as lean as it can without causing detonation (knock), so the higher the octane, the leaner it can run before it hits detonation, which equals more power and better fuel economy.

With all that being said, there are 2 rules of thumb. Always run high octane on forced inducted cars (they almost all require it) and don't waste money putting high octane in cars that do not state that they require it, that is just throwing money away with zero benefit.

I think it was popular mechanics years ago that did the math showing that the lower cost of 87 at the pump actually cost more than premium due to the loss of mileage on cars requiring high octane.
Issues:
1) The car does state what fuel it requires, and that's 87 octane on both the 2.5 and 2.5T, even though the former is high compression and the later boosted obviously. The trick is direct injection under high load, allows them to get away with lower octane than would have been possible without.

2) When detecting knock, the vehicle can compensate by running rich, reducing fuel economy, but not only is this not going to happen on 87 octane due to #1, but unless you are towing a heavy load or driving very aggressively even vehicles that do require 93 octane will be in low load states most of the time where its not going to ping anyway.

For example, most vehicles require about 20hp to cruise at 65mph, so for the majority of my commute where I'm on cruise control even running a lower octane than recommended by the manufacturer (which isn't possible on the SC in the US where minimum is the recommended 87 octane), you would see no change. This is why on our Mercedes that does recommend 91+ octane, when we went cross country where we were just chilling for hours at a time on cruise control we just put in 87 octane as it would have been wasting money to put in higher, but for normal day to day we put in 93 octane especially in the summer because even if we don't race the engine to high RPMs you can lose a lot of midrange torque running lower than recommended.

That said, its not easy to totally drain a fuel system, and so no one has tested the new 2.5T back to back on the same dyno on 87 and 93 octane to see what power difference there is, if any. The mapping may be flexible enough to take advantage of the higher octane even without Hyundai having specifically tuned for it, but I can't see myself paying the huge difference for premium without proof the power is drastically higher. For example, Honda recommends 87 octane for its turbocharged CR-V, but C&D tested and found torque was identical but horsepower increased 8hp which is such a small gain its not worth it. The F-150 they tested though where Ford does recommend 93 octane, it made 20 more horsepower on 93 vs 87 which IMO is worth it.
 

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2) When detecting knock, the vehicle can compensate by running rich, reducing fuel economy, but not only is this not going to happen on 87 octane due to #1, but unless you are towing a heavy load or driving very aggressively even vehicles that do require 93 octane will be in low load states most of the time where its not going to ping anyway.
Agree with you, except that the main way the vehicle's computer compensates for knock is by advancing the timing, as opposed to richening the intake mixture. Fuel mixture is adjusted continuously by the fuel management system, though, so mixture may also be jiggered.
 

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You're saying when the SC senses knock it advances the timing? Please show proof of that, please.
Usually the other way around, and the timing gets retarded (or, spark challenged, not sure what the PC term is /s), and the knock sensor is just one tool it will look at all kinds of sensor info including the O2 sensor and temps and so forth and there are all kinds of map adjustments it makes... and there's a technical name for it that I watched in a documentary but I forget now, but basically its not just a knock sensor detecting knock so retard timing this amount, its usually more complex and constantly monitored and will "learn" itself into the best timing/fuel/boost/etc maps so its not just retarding timing its tweaking all kinds of little things to achieve the desired result while maintaining best emissions, fuel economy, power.
 

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Yes, exactly as I stated above...

The timing is always advanced as far as it can be by the computer until it detects knock and then reverts the timing until there is no knock (retards), hence the octane levels coming into play. Your AFR's are mainly controlled by your O2 sensors. Other components also affect fueling, but the O2 sensors are the main component adjusting your AFR's. This is why when O2 sensors go bad, the computer instantly runs rich. Higher octane (yes even on the highway and not under load) will allow you to run leaner AFR's as determined by your O2 sensors.

Again, everything stated above is only applicable for cars that are designed to run higher octane, otherwise, you are just wasting money at the pump. I have not been able to get my Santa Cruz yet, so I can only go on what has been posted here for fuel requirements, which I have been told is 87. If that is the case, octane should not matter. If you plan on running any aftermarket tune (like a JB4), octane will then matter depending on the tune you are running.
 
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