Is premium gas worth it?

[dwightdi]

Premium octane gas ignite (or auto ignite) at higher temperatures. Lower octane gas self ignites at a lower temperature. Higher compression ratio engines cause low grade gas to self ignite and cause what is called "ping". Engines that ping on acceleration or climbing a hill are causing damage to the engine. Use higher octane gas if your engine is experiencing ping. Using off grade gas with lower detergent additives cause deposits in the engine and can cause carburetors or injectors to foul.

[Moflash]

Newer engines designed to run premium fuel will automatically retard the engine timing below the point of pinging (predestination) thus reducing the engines power output and will in effect rob you of gas mileage.The Ecoboost engines are a prime example of this.So by burning regular in these engines you are not gaining but losing.


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[Wolf Alaska]

Originally Posted by gomotomoto

We have a 2003 Toyota Sequoia and trying to figure out if premium gas is worth it while towing. What do you think?

If every gas vehicle was high compression & used 93 octane gas, fuel consumption of the USA could drop by 15%.

If your vehicle does not have high comp pistons, high octane fuel effects will be lessened. If the engine CPU advances the timing to the point of valve knock, then high octane fuel still can yield more power or economy.

I run pure 91 or 93 gasoline & set up the engine for high octane fuel:heavy towing when towing a trailer. (Recently saw 10.7 mpg)

When not towing, I run 87 oct. pure gas & set the engine to economy. (usually average 13.8 to 14.4 mpg solo)

Excursion 6.8L V-10 4X4
Let's Roll !
Wolf

[Moflash]

Premium fuel in a 2003 Toyota Is not needed and of no benefit.


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[Sodbust1]

Our 2012 Hemi Ram gets better MPG using the cheaper gas when empty and not pulling anything,, but we do upgrade a level when pulling as it will rattle the pistons at lower rpms other wise. Sodbust

[FunyFarm]

Ok to dispel myths about Premium or 92 octane gasoline, 1: if the mfg says use it, then use it. The timing on the engine control ( nowadays a computer function) has been set for optimum performance at ASTM 92 octane.2: and I know I will get flack from this but I do know of which I speak 20 years testing motor fuel quality on a field test basis for a state agency, and 15 years in the retail side of the gas business, BUT I DIGRESS, where was I oh yeah 2: dispelling the other myth premium burns colder , not hotter and one auto manufacture Dodge will tell you if you are towing and it is hot outside to burn higher octane fuel to keep the temperature down, this is good advise but Dodge should have addressed their engineering problem instead of telling customers of a workaround,, you Dakota owners with the v8 know what I'm talking about. 3 Myth I get better economy using premium,, short answer see number one. Long answer the difference in octane from 87-92 ( non mountain states fuel) is so minimal that it makes a non noticeable difference ( as in run a 1000 gallons through and you might add 0.5-1.25% increase, same road same conditions etc etc, so this is myth although true, is a non issue) nuff said

Bottom line ,, towing in the desert use premium if your Tv calls for 87 octane engine will run cooler. If your rig calls for 92 then burn 92.
Alluminati not all conspiries are theory

Now a Not so Short note about. 89 or blended fuels, when unleaded fuel was introduced to the industry there were 2 tanks in the ground 90% of the stations in the country sold. Regular and Ethel. The phasing out of the leaded gasoline during a time when most cars still needed the lead to protect the valve seats. Caused the need to have a third tank installed so there was leaded and unleaded, and ethyl. Follow along here for a second. Once the leaded gasoline was gone you had an extra tank in the ground. Our friends in the petroleum industry decided we need something in that tank, 40/60 blend of 92/87 octane brought it to 89. This is where they perpetuated a big fraud and told us our 87 burning cars would run better and we would get better fuel economy. ( bald face lie) now for the kicker forty years later there is once again just 2 tanks in the ground with dispensers that will blend fuel at multiple ratios up to 14 different blends available to the customers. Lol 14 come on the spread from 87-92 is so small this is a joke,, just my humble but correct opinion.

[jcl]

Originally Posted by FunyFarm

Ok to dispel myths about Premium or 92 octane gasoline...

Just a few things to add. Another (mech) engineer, ex fuel supplier, who once upon a time ran a single cylinder test engine in a lab to determine octane number.

Engines don't require a single grade, and operating conditions make a difference as well. Summer vs winter, altitude or sea level, engine clean or not, and so on. So the manufacturer specs a recommended AKI to cover all the bases. The real world is a continuum. So some will need that 92 at a point in time, and others won't. My BMW M54 spec'd 91, but ran great on 89 at my altitude, with my driving pattern. No retarding of timing, same fuel mileage 89 or 91, for the 80,000 that I ran it. When I travelled I used 91 because I didn't know the local fuel suppliers, so it was safer. A later model BMW with twin turbos ran fine on 89, but ran better on 91, and really came alive on 94. The stock engine tuning could take advantage of the higher AKI. If all that sounds too complicated, and particularly if you don't measure and log all fuel purchases, it is easier to go with what the manufacturer says. Suboptimal, but easier.

Next variable is the amount of additives/cleansers etc in the fuel. Some suppliers put more in the higher grades. That can make a difference.

Most important variable to me is the amount of ethanol contaminating the fuel I purchase. They have to put x% ethanol in by law, but not by fuel grade, rather averaged over all sales. So they put more ethanol in the cheaper grades, at least where I live. The blending pumps can put 10% in the 87, 5% in the 89, and none in the 91, for example.

When I find premium with no ethanol, it pays for itself due to the improved mileage relating to no ethanol, with the AKI not impacting it. That is at my local (high) fuel prices. I buy 94 with no ethanol over 91 with ethanol, getting no benefit from the higher AKI but covering the up charge for it with improved mileage. YMMV.

Jeff

[NC Camper]

Originally Posted by nrgtrakr

I enjoyed this ...
Regular or Premium? - Feature - Car and Driver

nrgtrakr, thanks for sharing the link. Seeing the science behind the regular vs. premium issue helped me finally made sense of the debate.

Originally Posted by FunyFarm

Ok to dispel myths about Premium or 92 octane gasoline...

FunyFarm, thanks for sharing your real world experience and knowledge, which supported what was in the Car and Driver article. Sometimes it is a challenge to sort out facts from opinions.

Happy New Year to all!

[nrgtrakr]

You're welcome.

[ROBERT CROSS]

My 2 sense.....if your hi-test is e-free use it..

Corn in petrol is a myth long perpetuated, better used in syrup to rot your teeth.....


Bob

[Jim Arnold]

Premium keeps the engine running cleaner and better performance I have found.

[J. Morgan]

Some folks get it, others do not, but in either case, the opinions run just as strong.


Brevi tempore!

[Gearheart]

All of the reg. vs high octane arguments I have read in the thread were valid back in the 70's before ethanol was mixed into the fuel. Back then premium fuel had less energy per pound than regular but was needed in aircraft and high performance cars to prevent detonation. Ethanol is the issue nowadays as it has way less energy in it than gasoline. When they dilute the fuel with ethanol, the performance suffers. You have to refuel more often, as you use more fuel to do the same job. Premium fuel, here in Canada, is not diluted with ethanol for the most part. Regular "may contain" up to 10% ethanol. If you can find non ethanol regular run it. If you can find non e premium at a good price run it before 10% e regular.

[DKB_SATX]

Originally Posted by MelGoddard

~~
My new Ford-F150 EcoBoost calls for regular also.
Seems to work ok.

The EcoBoost is one engine that doesn't REQUIRE higher octane but can potentially benefit from it. If you're towing, especially in hilly terrain, the engine can take advantage of premium fuel (and the manual tells you it's recommended in those situations.) It won't hurt itself on regular, but in high-load conditions it'll produce more power on premium fuel.

My Subaru's 2.5 liter turbo engine is similar, though more primitive. If I'm just tooling along on the Interstate it's not working hard enough to need high-octane fuel, but I've been diagnosed with a heavy right foot so I generally always fill it with premium (as recommended by Subaru) so that when I do get boost-happy the Legacy will give me all it's got.

[aftermath]

Originally Posted by richw46

Toyotas typically were built to run on regular. You can put a higher octane in it but it won't run any better. Someone may perceive that they are getting better performance but without technical measurement it's probably just a placebo effect........

This. There is nothing wrong with running premium gas but, in most cases, it will do no better than regular. People are really into the placebo thing and when you spend more money on something then we quickly hear that this is much better than that. Airstreams are better than SOBs, Mac is a better computer than a PC, a Harley is better than..... and on it goes.

Then there are those who read about something or hear about a new idea and buy into it totally. Hey, if it is on the internet, it has to be true. I knew a guy once that read about increasing mileage by taping magnets to opposite sides of the gas supply line running into the carburetor. He drove his big family station wagon to Disneyland and told everyone that he had almost double the mileage as before. Didn't believe it then, still don't but he did. He never spoke of this again though.

[J. Morgan]

The short answer is,,,, unless the vehicle manufacturer calls for higher octane fuel, or unless we are talking about some turbosupercharger equipped vehicles, premium grade fuel is not worth the extra money that has to be paid for it.


Brevi tempore!

[rjack]

We have our 4th Tundra and pull a 25' FB. Premium gas modestly adds to performance and enhances mileage more than it costs additionally at the pump. This is over the last five years and 50,000 miles towing....based upon our style of driving....65 mph highway generally.....kinda Grandma Duckish. J and K