Super Unleaded test compared to Regular Unleaded:

[Ernie3647]

Time to stir up some controversy.
I think you’ll find this article interesting informative at least.

 

[UmALum1990]

Mid grade is 90% Regular unleaded and 10% Super Unleaded, mixed at the pump. I was told this by the owner of a gas station. Biggest rip off. Use Regular or Super, don't give the gas station more profit.

 

[homeofstone]

Time to stir up some controversy.
I think you’ll find this article interesting informative at least.

Good article. He did not mention that mid-grade is nothing more than 50 50 mix of regular and premium. I found this out by discussing gasoline grades with the local BP terminal guys here in Athens Ga.

 

[mtrot]

Using premium and non-ethanol since second fill up (1st was on the dealer).
Avg: 17 cty and 28 hwy.

Nice that you have been able to find non-ethanol gas in N. Texas! I'm in East TX and it's almost impossible to find it here. Maybe regular unleaded at marinas, but who is going to drive 10 to 20 miles to a marina to fill up with regular octane gas?

 

[Alwaysforward]

I concluded phase one of my test. I strictly use Mobil gasoline for this test and thought I would share my findings.

Car: 5.0 Ultimate RWD

Conditions: Sport mode 24/7 in strictly city driving of one full tank of each fuel type (Super Unleaded and Regular Unleaded).

Findings:

Burned 1 full tank in Sport Mode using Mobil Super Unleaded and got the following fuel mileage:

Onboard computer - 18.90 MPG
Calculated mileage - 17.40 MPG

Burned 1 full tank in Sport Mode using Mobil Regular Unleaded and got the following fuel mileage:

Onboard computer - 16.6 MPG
Calculated mileage - 15.22 MPG

I can drive 348 miles on a tank of Super Unleaded -vs- 304.4 miles using Regular Unleaded. This equates to an additional cost of $7.50 more Regular Unleaded fuel to drive the additional 43.6 miles I got with Super Unleaded.

Factor in the added cost per gallon (Super vs Regular) of $7.20 per tankful, I save .30 cents per tank using Super Unleaded -vs- Regular Unleaded.

I just refilled the tank with Super again and will drive using same conditions (Sport Mode 24/7 & city driving) and will report back. Once I complete that test I will do it all over again using ECO mode using both types of fuels to see what the out come is.

UPDATE

We made two road trips over the past few weeks so I could not do my follow up test regarding city driving but I did run two full tanks with and without Super Unleaded and here are my results.

With Super Unleaded in Sport Mode and City/Highway driving mix

• 20.11 miles per gallon - Calculated

With Regular Unleaded in Sport Mode and City/Highway driving mix

• 18.61 miles per gallon - Calculated

Both test were with Mobil gasoline and included both highway and city driving. Were doing another road trip with Super Unleaded today and will report back what we get.

 

[mf7lakes]

List of known non-ethanol stations in Texas..........http://pure-gas.org/index.jsp?stateprov=TX

 

[commodore]

A phrase not mentioned in this discussion is placebo effect. Like it or not people drive differently when they're testing performance parameters of automobiles.
Not one 'on the road test' mentioned could be really considered accurate unless it was scientifically controlled (none were). No drive is exactly the same when humans are doing the driving and repeatability is a fantasy. Every little detail of the test conditions needs to be exactly the same or the test will be inaccurate. There has been some terrific information in this discussion about power, ignition and so on throughout this topic from people that really know what they are talking about (we know who they are ) but until an A - B mileage/power test is done on 'the rollers' and under controllable lab conditions, "your actual mileage may vary".
The power topic is almost moot when direct injection engines and automotive fuels are part of the discussion. So far no seat dyno has ever been actually calibrated and butt horsepower isn't part of many road tests except perhaps at my local pub .
RB

 

[thompithak3182]

http://www.hyundainews.com/us/en/media/pressreleases/33807
ok, I got on this site but it does not state that hyundai used premium or regular gas. the manual states to use regular. are these numbers gained from premium or regular fuel. I have noticed a small difference in mpg when I switched from premium to regular. i loss 2 mpg going to regular. mixed driving, on reg is 20-21 mpg and on premium 22-23. I drive the same routes mon-thurs. usually get on interstate fri-sun. I was assuming they got 333hp from regular since the manual states regular to be used.

 

[thompithak3182]

A technique used to prevent the onset of knock is the high "swirl" engine that forces the intake charge to adopt a very fast circular rotation in the cylinder during compression that provides quicker and more complete combustion. It is possible to manufacture gasoline engines with compression ratios of over 11:1 that can use 87 (MON + RON)/2 (octane rating) fuel with the addition of variable valve timing and knock sensors to delay ignition timing. Such engines may not produce their full rated power using 87 octane gasoline under all circumstances, due to the delayed ignition timing. Direct fuel injection, which can inject fuel only at the time of fuel ignition (similar to a diesel engine), is another recent development which also allows for higher compression ratios on gasoline engines.
doing some more research. the v6 gdi lambda engine has a compression ratio of 11.5:1...its safe to say that hyundai probably used premium to get their numbers?

 

[Alwaysforward]

Road trip yesterday using Super Unleaded and in ECO mode we got 23.33mpg (calculated). Not too shabby for a 5.0 with 420HP...

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[DRS]

sub'd. This is awesome because nobody believes I get better MPG from Premium even though I have the data to back it up.

Keep up the good work!

^ +1

 

[Alwaysforward]

I put regular fuel in on last fill-up before coming home from across the state and will be refilling it up this morning to compare against Super Unleaded. Will post findings at lunch time today.

 

[litesong]

Regular(87 octane) 10% ethanol blend contains 114 octane ethanol. To obtain 87 octane 10% ethanol blend, the gasoline component is only 84 octane. No wonder, 87 octane 10% ethanol blends don't work right in the Genesis & premium gives superior fuel economy! In other words, get rid of the 87 octane 10% ethanol blend by using 87 octane 100% gasoline(no-ethanol, E0) & you will raise octane by 3 points.
Some posters here are talking about premium fuel while some posters talk about ethanol-free fuel(E0), which is leading to confusion.
A less confusing discussion, NOT dealing with regular/premium fuel comparisons, but with 10% ethanol blends/100% gasoline(E0) comparisons, is on the thread: http://genesisowners.com/hyundai-genesis-forum/showthread.php?t=14483

One of my posts from the thread:

Beyond the 3% energy decrease of ethanol, ethanol needs high compression ratio(16:1) ethanol engines to effectively release its energy. Ethanol used(not burned effectively) in low compression ratio(9:1 to 12:1) gasoline engines cannot release its energy effectively. I have many years EACH, comparing 10% ethanol blends to 100% gasoline(E0) for 3 cars, showing 8%, 7%, & 5% increased mpg with E0. All engines run smoother, quieter & with a trace extra low rpm torque, such that less downshifting is necessary when ascending hills. My present 2013 Elantra is showing the same effect, of 8% mpg improvement burning E0 vs 10% ethanol blends. FYI, my Elantra has many complaints of low mpg & finally had to be downgraded in EPA mpg ratings. My present AVERAGE using E0 is 39mpg, with 15% city driving.

In essence, this post proves that ethanol engine engineers & gasoline engine engineers know how to design their specific engines.....using either 100% ethanol or 100% gasoline(E0), but NOT mixes of ethanol & gasoline(E0).

 

[Alwaysforward]

Road trip yesterday using Super Unleaded and in ECO mode we got 23.33mpg (calculated) on both city & highway driving. Not too shabby for a 5.0 with 420HP...

Update - Using Regular Unleaded in ECO mode we got 21.20 MPG (calculated) on this past road trip combining both city & highway driving.

Compared to above with Super Unleaded, it was a cost difference of only $4.26 more to use the Super Unleaded but I can drive 43.24 more miles per tank using Super Unleaded in this case study.

I refilled with Super Unleaded this morning and kept it in ECO mode so providing no road trips (highway driving) this weekend, I should be able to get a comparison against regular unleaded fuel (with 10% Ethanol in all cases).

 

[litesong]

A technique used to prevent the onset of knock is the high "swirl" engine that forces the intake charge to adopt a very fast circular rotation in the cylinder during compression that provides quicker and more complete combustion.

My inexpensive small 1979 Plymouth Champ 1.4 liter non-turbo 65HP engine had a small secondary intake valve (most cheap engines had one intake valve). It would activate at low rpms with little load, while the main intake valve would remain closed, more actively swirling the gasoline-air charge for better mixing. Often gaining mid-40mpg, the Champ gave 50mpg on a 1000 mile leg of a vacation, which, at the time, was the EPA steeply inflated MPG rating for the Champ. My previous 1.4 liter really small 1973 Subaru never gave over 36mpg, which was OK mpg, back then.

 

[Alwaysforward]

My conclusions are that I will continue to use Super Unleaded. On an overall average between city & highway driving with my 5.0 Ultimate, I get right around 21 mpg (calculated) using Super Unleaded. Where else can you buy and drive a 5.0 with 420 hp and get that kind of mileage. GO HYUNDAI

 

[jimb100]

My conclusions are that I will continue to use Super Unleaded. On an overall average between city & highway driving with my 5.0 Ultimate, I get right around 21 mpg (calculated) using Super Unleaded. Where else can you buy and drive a 5.0 with 420 hp and get that kind of mileage. GO HYUNDAI

I agree with your results and, for a couple dollars more at each fill up its well worth the money to use super.

 

[soldonandy]

I used to be really into home theater and this reminds me of the debates about if different speaker wires make difference. The science crowd would talk about capacitance, resistance and induction but I still preferred fancier interconnects on my big, beautiful and expensive speakers. I also used to drive BMW, Lexus and Mercedes and wouldn't consider anything less than the highest octane.

Since the economic downturn, my values have changed and I get great pleasure out of well built, less hyped speakers as well as basic constructed interconnects, some would argue that my sound system sounds even better today with less money invested.

As for my car choice, it is a Genesis and I take pleasure in the compelling value it offers in terms of high performance and luxury. The common sense information suggesting that not wasting money on higher octane gas fits more in my evolutionary perspective of value proposition and most likely the typical Genesis owner.

 

[2011 Genesis 4.6]

personally I am going with mikec, The fact that this is a 10:1 compression engine and has advanced timing giving it more HP and fuel economy (to an extent) if you run lower octane you will have the timing retarded and while that will run it will not perform as well.
And lets take into account any and all performance mods people have done from exhaust work to intake those differences could be compounded.

For example Stock 2011 power on premium is 385hp with intake and exhaust mods I would not be surprised if your getting close to that 400hp mark but if you put 87 in your dropping that back down into the low to mid (if your lucky) 380's.
Now thats just my opinion I dont have a dyno or a way to test this.
This of course doesn't really compare to does it save you money to run premium, though im with Alwaysforward on this the likely hood is over the course of the fill up you save a whopping $0.30.
This is more a matter of if your going to buy the V8 for its better performance why shoot yourself in the foot and run 87 octane?

 

[DavidA5913]

Don't know if this helps, but I for 27.6 MPG on the highway during a long trip using 87 octane. Car is a 2015 Ultimate allwheel 3.8