Is Higher Octane Fuel Better? Better MPGs? More HP? Let’s find out! 

You are RU-vid's gold standard for fair product reporting and always have been..no bullcrap,no windbag opinions,just very concise facts.👍👍👍

Only makes a difference if the engine can advance the ignition timing to make use of it.

This man is a world treasure and must be protected at all costs!! Thank you PF for all your hard work and dedication!!👍👍

My buddy who ran a motorcycle performance shop had the same conclusions using a dynamometer. He also mirrored Todd's advice: Unless your application requires it, or has signs of pre-ignition/detonation, just use the 87 octane. Well done as usual Todd!

Let’s be honest. For the second test Todd just wanted a good reason to drive his go kart

Octane is really about preventing Spark knock/ping and pre-igntion. These things are controlled by compression ratio, variable valve timing and ignition timing. With that being said, a great evaluation would be with a modern vehicle that truly benefits from using premium and or mid-grade. Also consider that many two cycle equipment have an 89 octane requirement. 87 is typically perfect for most cars and mowers. Not surprising that it worked well. Changing the ignition timing is a good upgrade from the previous test.

I agree with your findings with one notable exception.... In items like generators, pressure washers, etc that are small carbureted engines that are not ran often (or really any engine that is going to let fuel sit in it a long time), ethanol can be petty hard on those engines. Also some air cooled engines in some environments can run pretty hot, and then the higher octane can help prevent predetonation. I am a mechanic and I see what that does all the time. That said, things like my lawn tractor, regular passenger car, even my carbureted F150 truck gets regular 87 octane since they are used more often. A good rule of thumb beyond fuel stability would simply be keep in mind that octane is not a measurement of power or potential energy...its the resistance to knock. You mentioned turbos, but more or less any high compression engine should probably be using higher octane fuel.

When I was a young man,I used to use low octane fuel for my lawn and garden things,I always had a little trouble cranking things after winter.I switched to 93 octane,for my lawn and garden tools,never had another problem after winter storage.

I used to own a performance shop and did a lot of ecm dyno tuning. Most cars have 2 tables for ignition timing. They are for low and hight octane. It works off of the knock sensors. It will normally start in the high octane table and if it experiences any knock. It moves to the low-octane table. So by putting in high octane. you end up with more timing for more power and fuel efficiency

You're correct on turbocharged engines equipped with knock sensors. Premium fuel will make a very signficant difference on these engines which have been calibrated to run more spark advance and higher Manifold Absolute Pressures with leanest possible Fuel/Air ratios. When I was a Engine Development Engineer with a major OEM, we had to develop two calibrations for production - one for premium 93 and one for regular 87 (R+M)/2. We had a feature to protect the engine if the customer misfueled the vehicle and put regular in. The knock sensor output was monitored by the engine control system and all of the injector pulsewidth, spark advance and wastegate duty cycle maps would quickly revert to their predetermined values for the regular calibration. This was re-set after three discrete key cycles on/off. If the customer filled up with premium, the software algortihm would swtich to the premium calibration. The torque and horspower difference between the premium regular calibratins was huge when we did our power runs on the engine dynamomter and corrected to SAE J1349. Lastly, pure gasoline has more enthalpy than ethanol per unit volume. All things being equal, one should achieve better mileage on pure gasoline vs. gasoline+ethanol. Again, people should just read their owner's manual and follow the fuel recommendation there. Great video and thank you!

For those discussing winter storage of lawn and garden engines, always pull the spark plug and spray some fogging oil in the spark plug hole before reinserting a New and properly gapped correct spark plug. Add BOTH Stabil 360 & Star Tron Enzyme fuel additive into the gas tank and it will not matter if you use 87 or 91 octane, even if they both have 10% ethanol. Been doing this for years with perfect success 1st pull starts every time, even after sitting all winter (or spring, summer fall for the Snowblower).

i remember watching you back at 100k subscribers. me and my brother would always watch the vids. still here years later making straight forward informative content. much love

Your findings pretty much support what I learned in my 1974 HS Auto class. Higher octane fuel in a lower compression (carbureted) engine is not worth the extra cost. Thank you for this test.

Octane shouldn't make anything faster or more powerful unless the engine is designed to adjust timing or has an anti knock sensor. So it'll be interesting to see your results.

Your thoroughness and attention to detail is admirable! Thank you

Long time follower. Great work. I trust your work. I don't say that often. I have a test. I have used Extreme Fuel Treatment (also called Fuel Factor X) for over a year tracking my fuel economy. It makes numerous claims, I only tracked my fuel efficiency but would be interested in the other claims. I tracked my fuel mileage for a year to account for seasonal changes (Vermont) and to establish a baseline. I then used XTF for a year. Then stopped using it for a year to confirm results. Without sharing my results, I would be curious of your results.

I know you put a ton of work into these videos, and we all appreciate it.

I'd like to see a test on the various gutter guard products to see which ones really keep the gutters free of debris but do the best job of water drainage.

I bet the government is really confused with your tax write offs 😂

I truly appreciate your efforts and details you put on those videos. Thanks 😊👍

👍 Thumbs Up to Cousin Eddie for taking a bug to the eye and still sticking around to advance the testing science!

Always a good day when PF drops a new video!

Another great video on a practical topic. Thank you (& the viewer who suggested it).

Always been a huge fan of your tests. Subbed!

Project Farm is the gold standard for these kinds of videos. The thoroughness is amazing. No chit chat, no BS, just the facts. Keep up the great work.

I always use non-eth gas in small engines. It's not about the power but more for the stability of the fuel. Also ethanol fuel is very prone to pulling in moisture from the air which just makes it go bad all the quicker and cause corrosion issues in tanks and carb bowls.

Great demonstration. I was using 89 octane, now using 87. Saves me money. Thanks!

I’ve had a lot of issues with gas cans. I would love it if you would do a video on the best gas cans. Some are too slow. Some break easy. Some are too complicated. Some are just weird.

A bar and chain oil comparison would be very helpful.

Another REAL advantage of no-ethanol fuel is for those of us not diligent enough to drain and clean carbs at the end of the season for mowers and snowblowers is that ethanol free fuel gums up less. Since switching to 91 ethanol free in my lawnmower for example I've never had carb problems while before with the same MTD lawnmower that I had to clean the carb every spring with 87 octane 10% ethanol fuel.

Love the detailed walk through of methodology. I'm not qualified to judge - but I'm sure after years of feed back, you cover all the angles you have caught flack for before. I have confidence I can trust the results of the testing. Great info!

Thanks for taking the time for this test .

the fact that you are putting out at least a video a week is incredible. i can only imagine how hard you work to provide this to us. best channel for watching before sleep!! haha.

Would love to see this test with 1 year old fuel and some with stabilizer.

That's a pretty amazing video and test lots of detail appreciate your hard work..

I did similar testing 30 years ago with f150 that had carb and distributor ignition. Higher octane fuel allowed more timing before detonating. The increase in mpg due to more power at lower throttle made up for difference in fuel cost at that time. However, due to manually advancing the timing, I’d have to readjust it before running lower fuels again

I run the non-ethanol in my small lawn equipment to preserve the life of the carb and other parts that alcohol eats. Great work!

Usually octane rating doesn't matter on low compression engines. On higher compression engines, the higher octane can make the engine run more efficient and more powerful. Car manufacturers are almost at the point where they need higher octane on these engines in order to reach the cafe fuel requirements set by the government. Great video!

Great video as always. After switching over to running AMSoil engine oil I'll never look back. Would love to see a video on gear oil for both differential and manual transmissions!

Quickly became one of my favorite RU-vid channels. Been on a tear catching up to all the videos. Very informative. Keep it up. You're helping all of us

The effort that goes into these tests is nothing short of impressive.

“Cousin Eddie wanted to be in the action”… 😂😂 Todd, you never fail to make the info entertaining! Can’t thank you enough for all you do for us!

Great information...Thanks for taking the time to test these different gasoline levels!!

Outstanding yet again! Had this question just today while driving my Chevy pickup truck. 87 octane was suspected to be on par now this proves it. Thank you.

This guy test things I have always wondered about myself. And then you see his videos and are like " why the hell hasn't anyone tested this stuff or done a review " I love the content and applaud you for your dedication and consistency. These videos are not only entertaining but also educational. Keep it up and I will be subscribing. 👍

Thank you for letting people know that 93 is a waste of money UNLESS it requires it thanks for you’re videos.👍

Great video! You certainly put alot of time and effort into these. Thank you sir. I have subscribed.

I would not expect to see any performance differences in terms Octane. The true test would be a long term study of the affects of ethanol on the rubber parts of the carb. and any rubber seals. As mentioned earlier Octane won't really affect much on this type of engine. as always excellent job!!

Video idea: dry pour concrete vs traditional wet pour. I don’t think anything has done 28 day cylinder break test comparison. Would also be good to make samples and cut them down the middle to show the difference in how they cure. Thank you sir and keep up the good work!

I absolutely love the pure data of this channel. No bs yt fluff. No dragging on for 5 minutes just to make people watch (it doesn't work, we click away). I legit watch for the pure information provided. They area great. Well done my man.

Your time and effort are appreciated on all the videos. How about a video on stored gas in say one gallon containers? Something like 2,4, and 6 months. I have always heard that gas loses octane the longer it’s in the container. Kudos and please keep up the great work!

Thanks Sir For the hard work 😊

It would've been interesting to see how much you could advance the timing before you got knock on each of the fuels. Higher octane fuels are generally more suited for high output applications, so would've been cool to see that more

This guy is the best and I always appreciate the work he puts into his tests.

Love this guy's videos, takes a lot of time to perform these tests and I really appreciate it!!

Another great video. Thank you! I don’t recall if you’ve done this already, but it would be interesting to test different size impact sockets on stuck bolts. My recollection is that an impact socket with a greater mass should be more effective with the same drive tool than an impact socket with less mass. Like many others, my interest is in buying the best tool at the lowest price with a preference for tools made in America. Thanks again!

I remember when this channel was ten times smaller in terms of subscribers. We love your hard work and your recognition is well deserved. Well done!

I was recently looking at baseball bats for my son. Seeing the huge variance in price it made me think of this channel. That would be a fun comparison to see what a high end bat actually does different than a cheap bat.

I use 93 E0 in both my 2019 Ford Ranger Lariat and my 2020 Chrysler 300S 5.7. Both manufacturers state in the owner’s manual to use the highest octane available for best performance and fuel economy. The Ecoboost Turbo 4 can use 87 but runs noticeably better on the 93. 89-90 is the minimum recommended for the Gen III 5.7 but also runs noticeably better on 93.

My favorite part is the upgraded flywheel key. And it is neat to see the results of the tests with different performance levels of the same motor. All in the name of science of course.

You know it's a good day when Project Farm uploads

I appreciate the heck out of the thorough way in which you evaluate products. I think it's very scientific, in that the experiments are consistent in methodology and repeatable. Plus I like the fact that you don't just give us conclusions, you "show us your work."

Thank you for the video It was very knowledgeable

This crazy Test blew out my mind dude! Bravo 👏!

The ammount of time and resources you pour into your videos is remarkable, thank you for all the effort and dedication you put into them for our entertainment and convenience, Ive been able to make smart purchases and save tons of money thanks to you, much props to you sir!

Depends on the motor. Then the additives can make a difference too, negligible or not.

The quality, design and thought behind these tests are absolutely insane! Who would have thought of the residual fuel? Well, Todd, of course!

I love how controlled your tests are. However I wonder how running multiple 87E octane fills versus no ethanol will fair with carburetor buildup. Especially in the small engines like that Honda generator

Would be interesting to know if the top tier fuels have more detergents or any other additives than regular fuel

I feel like knowing the compression ratio for your equipment would be useful too.

I love your videos, they are quick, to the point and no nonsense. Love it!

I truly enjoy your channel because of your thoroughness!

You should test fuel stabilizers in regards to resistance to phase separation.

Your dedication in creating these tests is amazing, and very much appreciated, testing pump gas to racing gas would be interesting, Thanks as always Todd, you are the best. 🇺🇸

This channel and your methods and detailed analysis of everything is quite extraordinary ;)

Im sure I can"t say what has"nt allready been said. I"m a retired mech in the aviation field and have been labled the "MacGyver" of the shop. I can allways be found in my garage fixing and creating stuff. Bed frame rails are tempered angle iron and can be usaually be found free of charge to create and repair things with, I have a large pile. The product testing you do is invaluable to a do it yourselfer/ handyman. Keep up the good work...Dave

Consumer Reports has nothing on you but a bunch of expensive test equipment and a huge staff. Love your videos and your ingenuity in how to test things. Keep up the good work. I wish you well with your channel. Be safe!

You should test these in a very high compression engine! That's where one needs higher octane.

Man did you do a lot of work for this video! Thank you!

you are the wonderful guy. thank for the test alot

Could you test some coolers? They are so expensive these days I would really like to know which one would be best. What about possibly modifying a cheaper one to make it comparable to a higher end one? Anyway I love the way you test your products and do multiple tests so the results aren't just your own opinion.

This guy is definitely the cool uncle that everyone is excited to see and ALWAYS has a cool story to tell.

Great job on your tests... Nicely done... =)

Three things to consider: 1. Higher octane gasoline has a higher flash point and is less likely to result in pre-ignition (fuel igniting in a hot cylinder prior to spark) which can cause damage to engines over time. 2. Higher octane gasoline burns slower than lower octane providing power benefits in long-stroke engines due to the burn continuing across more of the power stroke. This can act as a drawback on engines with short strokes. 3. The major petroleum companies put additives such as detergents and anti-corrosives in their premium gasoline to keep your fuel system clean. Mid-grade fuel is a mix of premium and regular (the mid-grade pump sucks from both the premium and regular tanks at the gas station simultaneously).

Seriously, this is a masterclass in the application of the scientific method. I often fantasize about what our world might look like if this standard was applied so thoroughly everywhere.

Great test! good results too! I think the only advantage I have had with non ethanol fuels in a carbureted application is the lack of vapor lock. If you drive through the mountains in the summer time and you have a carb you might want non ethanol for that reason.

Great video keep them coming , for me 94 octane keeps my 11.5 comp sbc from detonating so nothing to do about it

Thank you for all the effort you put in these tests good neighbor!!

Your videos are the one thing I look forward to on Sundays! 👍🏼

The real difference between the different octane levels is how well they resist knock. This is most important when running a higher compression engine or when using boost, and neither of the engines you were using fit those qualifications.

Thank you for providing us with your experimental knowledge. This is by far the best channel for us the consumers when it comes to choosing the best option for a myriad of automotive, electrical, mechanical, civil, etc... Applications. When I come across something worth comparing I will suggest. But for now I refer to your videos for making the most optimal choices when buying anything you have made a test for. You sir are a scientist.

Love your channel, Thank you

Todd puts more effort into his tests than I put into my entire life... 👍🏼👊🏼🦖🍺

The octane rating of fuel is a compression timing. Its at what pressure the fuel will partially pre-ignite. Using premium in your corolla can cause damage. Only use regular gas unless your car says otherwise. As its only for ignition timing. Those 2004 Pontiac Grand Prix's required Premium. - Detroit.

Thank you so much, already learned something useful on the first day of 2024! 🤣🤣 happy new year to you all!

Great video, loved the detailed testing. Octane rating is pretty much just how much fuel can resist detonation from compression. Higher octane rating let's you take advantage of high compression engines and increasing boost from turbo/superchargers.

Glad to see your uploads again. I love how thorough and consistent the testing is in these

I can see where it would be better for high-performance cars to have higher octane fuel. But I’ve always ran 87% and all of my vehicle my dad always said he couldn’t tell the difference he thought it was price gouging. He may have been all right. Thanks for the video.👍🏼😁

Great test! Thanks Todd.

I'm a retired automotive fuel system designer. People get octane and btu confused. Ethanol has its place but has drawbacks too. I really enjoy watching these tests. Great job!