Does the Fuel You Choose Matter? | Engine Masters | MotorTrend

[@jasonlevitt]

Not mentioned but important- to use E85 you'll need a fuel system capable of flowing 30% more than if using gasoline. So, injectors and pump (at a minimum) will need to be sized for E.

[@SweatyFatGuy]

Some EFI systems have enough room with the injectors, from what I have seen Asian EFI does not, the injectors are sized very close to what the engine needs on gasoline without much room to flow more. Testing my LS engines I can run E50 and not get a lean bank code but the duty cycle gets real short. E30 works without a problem in most carbs, and does well with US made EFI. Until you throw boost at it, the pumps are usually adequate in domestic vehicles to run E85, so its usually injector swaps and a retune. With carbs its more than just a jet swap, main circuit, idle circuit, power valve restrictions, accel pump, all need a bit of massaging, but its not hard to do. Sometimes its 30% larger, sometimes its less, flow rates vary a bit through different sized and shaped circuits/orifices and at different pressures/vacuum. Air bleeds can make the mix go quite rich or very lean, so can float levels. I like to sneak up on it when I convert Qjets, because if you go too big the mileage benefit of the Qjet goes away. With a Holley, you're usually going more for power than anything else. Best power is not at stoich with alcohol fuels, since they are carrying more oxygen you can throw more fuel at it and pick up power... to a certain point. On E85 and NA best power is around 7.5:1 AFR, and best mileage is between 8.5:1 and 9.5:1. The cool thing about running E85 is you can throw a lot of boost at it, or run VERY high compression. One of my daily driver 455 Pontiacs has 13:1,the 65 GTO has 11.5:1, and the 505 I am building at the moment is just short of 12:1, but the 505 is probably not going to end up being a mileage mule, unless I want to get silly.

[@volvo09]

I remapped my car to e85 (diy) and the stock injectors were good (although getting high in duty cycle, around 90% so there wasn't much headroom left). I later supercharged it and surprisingly the stock fuel pump could still keep up! This was just a little Honda though. 4 1000cc injectors that flow roughly 850cc at my fuel pressure. Sadly I don't have access to e85 anymore (I moved) so it's back to gasoline. I daily drove e85 for years and 140k miles in that car.

[@BuzzLOLOL]

Also not mentioned is if the computer/knock sensor was pulling some timing out around torque peak RPMs on 87 octane gasoline...

[@drakrazerclaw5146]

I run E85 in a stupid little mini bike I have with basically an outlaw/unlimited 212cc race kart engine on it, and I need to drill the seat for the float needle. After about 10-15 seconds it bogs lean because the bowl is almost empty, but it's going about 60-65at that point so maybe it's a good thing. 😆

[@JaysPCImpossible]

most stock fuel systems can handle e85, the only issue is you will lose a lot of headroom on your injectors and you will most likely have to increase the fuel pressure on your fuel pressure regulator before changing out the fuel pump. But, it is recommended to upgrade to a system that gives you more of that headroom..

[@TL-angzarr]

On race engines it can get complicated. I have a 511 inch B1 motor with 15.2 to 1 compression that I ran forever on C14. Then a couple years ago my supplier had ran out of C14 but had some C25 in stock so I ran it. 2 more octane points but the car made its fastest pass ever by just over a 10th and on average was up by 5 hundredths with zero additional changes. Over time with tweaking the carbs the car gained a solid .125, gains like that are huge going from 7.90's to 7.70's with such a simple change.

[@magnumcipher4971]

15.2:1!!! Wow. What do you crank that thing with? A small block? 🤣

[@terriblatgaming9554]

@@magnumcipher4971. 15:1 is right there with the compression levels of a Diesel engine. That’s really impressive for a gasser

[@TL-angzarr]

@@magnumcipher4971 That's with flat top Pistons too. The heads have been flat milled to 50ccs. It's not particularly hard to start. The car has 2 batteries because I don't run an alternators,still at 12 volts tho. I spin it with the starter a couple of times before turning on the ignition and it usually fires right up.

[@user-vl2zh6bj6x]

@@TL-angzarr that sounds like a Boss Hog of an engine you created. I'd like to see a video of your runs/ passes.🤠🏁

[@steelervette]

@@magnumcipher4971 🤣🤣

[@CarsandCats]

I thing I do know is that when you run 110 in the lawn mower it blubbers out the exhaust and runs rich, but smells great. I was too lazy to go to the gas station :(

[@hondafan163]

Huuuuehaaaat

[@volvo09]

😂

[@dimmacommunication]

If only race gas was so cheap I could use it in the land mower 💔

[@privatedata665]

2 years ago I watched an old guy ( like me) fill his lawn mower gas can with 110 ( station right near a race track ) I said "ya know 87 is a lot cheaper " he replied " this smells like I'm at the races "

[@user-vl2zh6bj6x]

@@privatedata665 just got 2 gallons the other day while Miami town Ohio near Edgewater drag strip for nine dollars a gallon. Surprisingly it has not changed an increase since all other gas skyrocketed due to planning>

[@alexfreund9460]

I love running E85 (with a flex fuel system and slightly raised compression) because in my area it's about a dollar cheaper than 87 octane. It's about a break even with the loss of mileage but if you need the knock resistance, it's a great value!

[@theMister07]

I’m saving over $2/PG running E85 over Non-E. E-85 is currently $1.979/gallon. With the current setup on my FFV, I’ve managed to match the C/H miles between gas & e85…V8 engine

[@SolamenteVees]

Love Engine Masters; they present the facts without too much minutiae and just enough levity.

[@SophiaAphrodite]

Until you get to reversing pistons.

[@MarioLoco03]

I had to look up the word "minutiae"

[@anubis8680]

@@MarioLoco03 Dont get hung up on the little stuff 😂

[@SolamenteVees]

@Nphekt 🙄

[@jimr5703]

I often find their methods of research somewhat less than scientific. There are sometimes variables completely ignored and/or unaccounted for.

[@tonymunn]

Very informative. I have a turbocharged Toyota 3TC engine running on propane. I'm sure it can't compare to any of those fuels power wise but, I can buy 500 gallons when it's cheap and It'll still be good a million years from now.

[@littlefoot2869]

Prop is best plus oil don't go to waste

[@ragtopdeluxezl1]

Our LSA/6.2 with bolt on mods was at 585whp on 91 octane add E85 and we are at 630whp...Bore and stroke to 6.8 and we sit at 720whp. A bigger blower and an inner chiller would help. E85 is the most practical fuel for hp gains in my application.

[@mikec3142]

Would have been a better test if the engine was boosted. You could show the detonation / knock values, along with the differences of the exhaust temperature of each fuel. Then you could run E85 and show how much MORE volume you need to match gasoline.

[@enriquesantanajr.4537]

I'd like to see boosted comparisons as well.

[@danwiththe8647]

they sort of addressed that, much like if the engine was much higher comp ratio, then there would be more visible gains in higher octanes. I would love to see another video where they do a comparison of boosted fuels and maybe even have the bench mark be the HP outcome. like to make 600 hp, how much boost per fuel or something like that

[@rogerhupp3115]

The point of the test is to prove that if you don’t have detonation with X octane, using higher octane won’t make a difference. It doesn’t matter if it’s forced induction or not. If it’s not knocking, it’s not knocking.

[@Dr_Xyzt]

I did a much more scientific video on my channel about this three years ago. The methanol engine will run cooler under certain circumstances.

[@boracay12]

The guy doing the video is using the wrong fuel for his body and to much of it .

[@tedbear631]

This show is one of my favorite things on KZbin plz more engine masters!

[@gtbmjb7192]

Excellent video. Focused and accurate info and well explained as to what the test's purpose is and that power adders change the outcome and that this is a dyno room controlled atmosphere not an under the hood application. Takeaway for me is "use the recommended rating for a stock engine." Thanks Engine Masters.

[@jake20479]

when naturally aspirated, unless youre running some crazy high compression.. octane wont make much of a difference. however.. once you apply boost.. that dramatically changes.

[@dimmacommunication]

Ethanol with a flex fuel system looks like a win/win situation. Cooler /cleaner to run ( with a decat car less smells ).

[@nordic5490]

Correct. Over about 15psi boost, and with decent advance, e85 is a must.

[@BuzzLOLOL]

@@dimmacommunication - But reduces MPG about 25%...

[@BuzzLOLOL]

Higher octane pump gas is just deadened 87 octane so it won't ignite too soon in a higher compression ratio engine... The higher priced race gases, of course, have higher power additives, as well...

[@dimmacommunication]

@@BuzzLOLOL Yeah I know...

[@jasonpace9260]

I could watch this show all day please never stop making it

[@calvinevans8305]

It's designed for 91 octane. That's an awesome street engine.

[@rileylilwell5201]

It would be cool to do this experiment with a boosted application, where the knock limitation does come in. I think there would be a WAY bigger variation in results👍🏼

[@blakebarry2756]

I'll let you know what the difference is in a couple weeks, going from 98 Oct unleaded to e85 in a supercharged stroker ls1 6.3l

[@TheNecromancer6666]

Our an engine with A compression ratio. Like 12:1 is a baseline for a nat asp usually.... I mean an RS5 runs 2,5 bar manifold pressure and 11,5:1.

[@Garf2O]

Stustustu boost leak engine takes a dump video over, exciting.

[@thegirthquake8574]

@@blakebarry2756 Following up on this, thoughts?

[@RedfishCarolina]

On a whim I decided to put E85 in my 1999 Vortec 5.7 Suburban. The resulting mix with the residual 87 octane would have been about 50% ethanol. Truck ran the same as it always did. I took it nearly to empty, refilled in 87,and felt nearly no change. Engine is 100% stock.

[@bongtoadboobender3921]

I did the same in my 4.3 vortec headed blazer with no noticeable difference so that was my experience to

[@AgentLokVokun]

These results is why I had a 67 Chevelle 427 SS converted to E-85. It may consume more gas but it's MUCH cheaper then the race fuel it's normally tuned for soooo.

[@SweatyFatGuy]

My 65 and 70 GTOs run on E85, with LOTS of compression in their 455s. The 68 LeMans runs E85 in its 461, and soon the 505 I am building for it. 79 Formula also runs E85, it has a 700hp 467 Pontiac. Around 12:1 compression I get better mileage on E85 than on gasoline, especially 87 octane. It makes a lot more power too. The 70 has been on E85 and home made E100 since 2007. 65 since 2018, 79 since 2010, 68 since 2014. The 79 has a fuel cell in it, the rest have stock tanks. Zero problems with it in all that time. Carbs and EFI... no problem I dont even bother building pump gas engines anymore.

[@steveshortt90]

In Australia.. our cheapest fuel is $1.85/L.. e10 is $1.83/L BUT e85 is $2.40/L. It's crazy

[@SweatyFatGuy]

@@steveshortt90 Considering you probably have it imported rather than made in country, that would make sense. Also if the government wants to keep you dependent, they wont allow you to make your own.

[@jessetrowbridge6539]

Great episode. Would love to see a low RPM knock test. Going WOT under load at 1,750 RPM. This is when I notice bad gas most...

[@SophiaAphrodite]

If you are getting bad gas. Use a different gas station. This is not bad gas. Just different gas.

[@danr9584]

High throttle under load is usually when cars ping (such as accelerating or going uphill), but on stock cars that is when the EGR will start to open.

[@marv8481]

It can be bad gas, any e-10 fuel can actually hold the same amount of volume of water as ethanol. And if it truly holds 10%eth, then it can also hold 10% water, and if it’s fully saturated the water can drop out with temperature or pressure changes. But if it’s near saturation but not dropping out, it’s probably causing a slight misfire, not pre det. Most factory built and tuned, unmodified cars won’t see a problem with 87 or 91 (where I live that’s regular and plus, premium is 93/94) under most operating conditions, even when really hot ambient temperatures occur. But you may start getting det with mods, or a tune, or the hand held tuners/chips under low rpm, high load

[@NBSV1]

The water brake style engine dynos don’t work well at low rpm. There isn’t enough water being pumped for it to load the engine down. You can make some changes to get it to load at low rpm, but then it may not work at higher rpm.

[@volvo09]

@@SophiaAphrodite "bad gas" could just be him saying lower octane than the engine wants. I used to put regular in my turbo car for long trips when I just burned through fuel. It would ping if I got into boost more than a few lbs. On a side note I was always curious if a service station would lie and sell regular as premium, or have some super sh1tty gas, but I never ran into it, I would have been able to tell instantly when I hit boost) in that car. It needed 93, even 89 pinged. (My area dosen't really have 91 so I never tried it)

[@mbhftw]

I've been on the dyno countless times and after tuning we mixed 109 to make 100 oct. 100 oct repeatedly beat out 91 oct in power numbers after the ECU adaptations took effect. This test might be legit for an LS motor, but i can promise you it is not on other motors.

[@SweatyFatGuy]

Not disagreeing with you, I am expounding upon what you said... chamber shape, compression, material of the heads/block, and engine design make a difference in how much octane an engine needs. So if you are getting inaudible knock that will cause a power loss. If you have to back the timing down, that will cause a power loss as well. If its a crappy combustion chamber design, that will affect timing a lot.

[@PoppinACap22]

I’ve loved this show for the main fact it taught me so much about “engine science” I guess you could say. I watched a lot of this show around the time I was building my first engine which was a TBI 350. I pretty much turned what would have been a borderline “stock” TBI i guess into one that would pull a little over 300 hp with more tq than intended. Can’t remember that number to be specific. I spent more money than what I needed to on a TBI but it’s knowledge I appreciate having now about them. In a time where a lot of people appreciate the 88-98 OBS Chevy trucks, its nice to have the knowledge to share with people and help them out with any issues, builds, and so forth.

[@HerculesRockefellerESQ]

We ran a coyote on our dyno where I used to work. Prototype test controls pack and whatnot. It picked up HUGE switching from 87 to 94, changing only the fuel. Somewhere around 25hp if I remember rightly.

[@Bacongrease00]

Folks forget many modern ECU will pull timing when the knock counts go up like when using lower octane fuels. engine will run but your leaving some performance on the table .

[@chuckselvage3157]

Octane isn't really about power it's about knock resistance.

[@jcoats1203]

Exactly!

[@ktmr8]

Pretty much on the money for what we found with the e85 switch… with 15rwhp increase at peak and greater gains in torque and power in the low and mid. Railway tracks from 2500 to 7100

[@julioaperales1228]

Man!!! You just got Robert Duvall from Days of Thunder to run the Dyno!!! That's the coolest thing I've seen!!!!

[@Funkydood]

I keep LOVING your experiments more & more!!!

[@mrsteve4313]

Would love to see this done with 3-4 different engines. Obviously the biggest difference between fuel is if the engine actually recognizes the difference in fuel.

[@willymaze368]

i'm not a engine master, But do they have to text everything on a 500HP engine?? Do it on a stock LS2 or something

[@michaelsantosuosso7284]

hey we all know what fuel does what, this is an anomaly in very set controlled conditions......heat and compression and the great equalizers here everyone and they do touch on that some.

[@Dr_Xyzt]

@@willymaze368 Dude, it's a cammed LS. Nothing special.

[@GETLITUP69]

It needs to be tested on 12.1 compression engine, that will show you the difference.

[@johnduncan9681]

@@GETLITUP69 exactly. Waste of time to go beyond 87 if the engine does not have a problem with it.

[@davek6089]

Had a customer asking me if he could Eva aviation gas in his old bmw e30, I said there would be no point. I feel exxxtra validated now! Thanks engine masters!

[@BearGFR]

Love this!!!! I can't tell you how many times someone has wanted to argue that more octane = more power, so thanks for providing the proof.

[@jerzey22]

Nope it’s just better knock resistance

[@sparkie5571]

generally it only allows more boost or ignition timing WHEN running into a knock scenario. absolutely

[@decnet100]

Well if you're using any charged engine, then it might well be. On an N/A engine, not so much.

[@BearGFR]

@@decnet100 Only because running a blower/turbo *increases cylinder pressure*, which is just like running a high compression ratio - in fact more so. Still, it's wrong to say that running higher octane "gives" you more power. What's going on in those cases, is because of the increased cylinder pressure the engine "NEEDS" more octane to stay out of detonation. The increased power comes from the fact the engine is having more air/oxygen crammed into it.

[@decnet100]

@@BearGFR 100% agreed, I didn't even think of it like that, as in the octane being the actual power. But as you mention it, I can totally see that this is probably a common misconception. :) My perspective is a bit influenced by another interest of mine, WWII engine development - where octane could in many cases actually be directly equated with power, as the engine could then very easily use higher boost (as simple as the pilot pushing the boost lever further forward), therefore the supply of high octane fuel was very important in winning the air war. Highly recommended vid from that perspective: kzbin.info/www/bejne/hHuzaJylqrKqqac

[@gordongrimes2797]

think about this it take more e85 then gas less room in the combustion chamber more fuel more compression Walla more power so its not just the fuel type there are other factors involved great video. thanks

[@ironmaiden5658]

Great video. I feel kinda silly now thinking back on all those years racing my street car down the quarter mile and stopping in to the airport on the way to get the super special Aviation fuel. And every time I used it I would tell everyone just how much faster my car is with the AvGas. haha. It literally only needed 91 for everyday use.

[@CarsandCats]

@Goblin Slayer Doesn't help. Watch the video.

[@ironmaiden5658]

@Goblin Slayer Yeah. Watch the video.

[@WhuDhat]

don't feel silly, you're definitely not alone. I knew a guy who did the same and swore by it for gains in his Honda

[@every-istand-ophobe6320]

@@WhuDhat yeah... H.old O.n N.ot D.one A.ccelerating

[@decnet100]

Well the more work and effort you put into something, the harder it becomes to admit that it doesn't have an effect. Don't blame yourself, it's human nature. Guess why people have such "amazing" results in non-measured hobbies such as audio - when you're opening up an expensive piece of equipment and start replacing components in there, which you researched for weeks, especially if you ended up getting rare cold war russian army space mission capacitors sourced from an ebay auction only accessible from Kazakhstan instead of some off-the-shelf stuff - then chances are, you're by then tricking yourself into thinking all that effort must have a large result.

[@johnbehneman1546]

GREAT VIDEO DAVID!!! I ALWAYS LEARN SO MUCH FROM ENGINE MASTERS. PLEASE CONTINUE TO SHARE YOUR TRUTH.

[@inertiaMS]

This doesn't really take into consideration how much you can beat up on engines with E85 vs pump, overheating, leaning etc etc E85 is so much more forgiving.

[@daesmith3274]

Steve is right again. Alot of the local sprint car/super mod circle track guys run methanol. They run the same oil all night in naturally aspirated 8-900hp small blocks.

[@gtbmjb7192]

Excellent video. As always it is up to us viewers to use the info correctly. I appreciate you stating that you would not change from the OEM fuel recommendations for street vehicles because of the underhood temps, etc. Very well balanced presentation.

[@backcountryme]

We run Methanol in our midgets and sprint cars because it is harder to ignite. It is a safety factor. In a wreck, it is less likely to catch fire. Indy cars ran methanol for years because of the same thing.

[@davekauffman8727]

A figure left out of the mix is MPG that the fuels are able to deliver. Ethanol has less energy in it compared with gasoline, as per other scientific channels, and may have been a more applicable number especially since fuel economy is quite important today.

[@hdrenginedevelopment7507]

“Economy” is actually a miles per $ equation. E85 often falls somewhere between 87 and 89 in miles per $ by the time you take advantage of its benefits in the calibration. Yes, it loses mpg, but it’s also more inexpensive and the knock resistance/flame speed/air charge cooling benefits can often offset a bit of the loss in energy density, so the net increase in consumption can be as low as maybe 20% instead of 30% based strictly on energy content. A lot of calibrations have to run richer, or enrich the mixture sooner under high power to control knock and to control catalyst temperature under the lower ignition timing advance that low octane may require. It’s all the little things that can add up.

[@Dr_Xyzt]

Methanol for the win! I computed the value over three years ago and did a video about it on my channel. 15% on the dot. Sweet. -- As for the corrosion, methanol has a lot in common with water. You open the door for dissimilar metal corrosion. If you keep the metals similar, you'll be in better shape. It allows electrolysis to happen, so your fuel pumps will slowly electroplate themselves to death. A brushless pump will work, or ideally, a motor at the top of the tank can drive a shaft-mounted pump at the bottom of the tank. -- The corrosion isn't a big deal if you build it wisely, and for easy maintenance.

[@Dr_Xyzt]

Well, it's been a year since I made this comment. My comment still stands. Methanol is a great replacement for gasoline. It's a simpler molecule so it burns better. If you're using a bunch of boost, then letting the engine sit for 3 months, that's your fault. For a hot-rod that gets driven periodically throughout the week and has a fuel system designed for simple maintenance, Methanol has a lot to offer. Plus, it has no particulate emissions. The methanol molecules are simple, so they burn better. I'm all for it.

[@colinsdad1]

Besides the higher flow rate for E85 being a necessity, I was hoping 93 and 100 octane (aka CAM2) would be tested, because both are available here on the East Coast. I guess this is a West Coast fuel test.

[@kleetus92]

While I appreciate the idea, I'm in western PA, so I feel ya, but what they showed with leaded fuel would replicate the Cam2 stuff for the same reasons... If you're not detonating now, 'better' fuel isn't going to do anything for you, at least in an NA engine. If you're boosted, and you can adjust it easily. Then yes, you'd see something.

[@torqueytorque8861]

So-called "CAM2" doesn't exist anymore. I'm almost positive the formula for CAM2 was acquired and re-branded by Sunoco as Sunoco Standard, which is one of the fuels tested in the video.

[@WalkingPanther77]

Engine Masters is definitely one of my favorite series to watch.

[@CarShowclub]

This test was a lot of fun. Never would I have thought that E85 and race fuel would be in the same video.

[@Treyk901]

E85 is the common man’s race gas. Just have to tune the engine to take advantage of it.

[@TechReviewbyIrdi]

Yes, I get a catalytic converter fuel burn issue code every time I run 87 in our Acura. It's supposed to be 91. But 91 has disappeared from PA in a lot of places. I have to go 93 to keep the code from coming up all the time. My Charger has a recent Hemi with MDS. It like 89 for HP, but can run on 87 with no problems. But at a very small HP price.

[@proximitybeejay3673]

You guys have to back this up with a boosted car comparison now. Im really curious too see the numbers with the same fuels again on anything boosted =)

[@Roboticpycotic]

Exactly. It world be completely different, cylinder pressures are through the roof compared to NA. I picked up 40hp going from e10 to e25 on my 1JZ-GTE

[@ouch1011]

I’ve tried to explain this to so many people who insist on running premium in their stock Honda Civics and Dodge Caravans. They’re just wasting money. Those engines would run fine on 2 year old 2-stroke pre-mix. Unless your car specifically calls for higher octane fuel OR it has some sort of mechanical issue that causes it to knock on regular gas, just use regular gas. I would have liked to see this test on a forced induction engine. N/A street engines don’t need much octane at all, plenty of N/A street engines running 12-13:1 compression on pump gas.

[@8E6JI]

I run 93 in anything from my built big turbo Evo 9, to all of my Hondas, daily Mercedes, etc. while over half of my cars won’t benefit from using 93, it’s a much cleaner fuel for the engine to burn rather than 87 long term.

[@ldnwholesale8552]

Two year old fuel struggles to light. It has turned to varnish and plugged up injectors and or jets.

[@lildno2007]

Octane only matters for HIGH COMPRESSION OR INCREASED CYLINDER PRESSURE UNDER NITROUS OR BOOST

[@SophiaAphrodite]

which they stated

[@brapbrapau]

Did you even watch the whole video?

[@Wes.berryman313]

Here in NC, my Ram 1500 Hemi dispises 87 octane gas but loves 93 octane from Shell. Just going back/forth to work, I get 2 more days on 20 gallons of 93 vs 20 gallons of 87. Plus better overall performance on 93.

[@mattbauckman9907]

High compression with small camshaft will definitely be different results. Having iron heads even more different results. Try a bone stock factory spec’d 396 with 87 and it will ping itself to destruction. The results would get impressively better as the octane numbers increase. This combo they had here is a sweet setup as you could run anything from any pump at any station and it will live.

[@RedfishCarolina]

Pardon my ignorance, what would a factory stock 396 been used in? I assume this is something designed to run on 91+ right?

[@mattbauckman9907]

@@RedfishCarolina A restoration of a 100% factory original Chevy that was equipped with that engine. Millions of Chevy’s from 1965 to 1970 were equipped with some version of a 396 cubic inch big block. Most were required to run on 97 octane or greater.

[@josephmiller9434]

Hmm not sure how much power you would get running diesel in a high compression gas engine 🤣

[@mattbauckman9907]

@@josephmiller9434 Since diesel has an octane rating of anywhere from 25 to 40, I’d say it would run horrible to not at all. Anyone who’s ever somehow managed to get the nozzle to fit and actually pumped diesel in their tank will know that it doesn’t work very well. 😆

[@DTechnologyservices]

Listen to me: If your car call for 87 use it. The speed you looking for is based on upgraded air filter, This one is important: HIGH STALL TORQUE CONVERTER AND HIGH PERFORMANCE TRANSMISSION REBUILD, high performance fuel filter, high performance throttle body spark plugs and ignition coils, high performance coolant, and finally high air flow exhaust system. This is when you realize 87 octane is beautiful. If your car don’t have all this then don’t get mad when the performance is trash. And if 93 is making an engine that calls for 87 run better then start putting the work in to make 87 run like 93.

[@F_________________]

I’d say more octane starts to make a difference with higher compression, especially with boost. The LS3 isn’t making high enough compression to make that much of a difference. It would be interesting to see how a Gen 3 Coyote motor would do with the different fuels.

[@copperlocks1]

I wonder if they used cast iron heads if the numbers would be different

[@Treyk901]

A tuned gen 3 using E85 will scream.

[@plark7323]

Only downside to coyote is cost compared to ls based.

[@F_________________]

@@plark7323 a lot of Coyote guys go with a Gen 3 truck block, Gen 2 heads and Gen 1 crank. If you do that you’re only spending about $3500

[@michaelsantosuosso7284]

I STILL CANT GET OVER FRIBERGER BEING 73 years old......I thought he was like late 40s early 50s when first watching ROADKILL......UNBELIEVABLE, GOD BLESS U DAVID.

[@carboswp]

He’s 54

[@brettjohnson8009]

He was born in 1968 ,you do the math

[@kleetus92]

I hope you build engines better than you do math...

[@randallrougeau530]

Thank you for Engine masters David Fryberger next to roadkill episodes this is the one I love the most

[@josephmatuszak3855]

OK, now do it with a supercharger @ 12lbs of boost. Also, I would very much like to know the engine temps on consistant load as well as the emissions and particulate results.

[@leftyeh6495]

I think you're in the wrong place for emissions testing. Ethanol does nothing for the environment. It does boost octane.

[@DavidGreig-w2h]

I notice when I use 94 octane & mix with a 110-112 octane 50/50 I have better throttle response & revs up harder to max RPMs . Plus the premium fuels have the additives that help

[@dirtbike662]

Octane is resistance to knock. The additives are added or not by the different brands or gas stations. Look for "top tier" gas for the additives.

[@sketchpv3080]

Summary- this low compression NA motor is a beast on 87 octane!

[@ohhthepatpat]

10.7/1 compression wouldn't be considered low compression.

[@kevin9c1]

@@ohhthepatpat It is for a "built N/A" engine.

[@mrmedium7984]

@@ohhthepatpat Depending on the piston crown shape, it is

[@BuzzLOLOL]

Aluminum heads. fast burn chambers, and computer/knock sensor allowing 87 octane... but prolly pulling some timing out at lower RPMs... reason 87 was down a couple lb.-ft. in torque...

[@1987FX16]

Got a ls3 in a Silverado and it likes 93 in the south Alabama summer heat. 110+ IAT/Ambient it knocks pretty easy on low rpm high load with 93. On 87 an easy 5-10° needed to be removed below 3500 above 37kpa and about 5° taken out above 3500. L9h Headers, ORYpipe, stock exhaust, 87mm TB port radiused, MIT tube and a modified factory airbox with ram air from the grille and a debaffle. It will run find on 87 but you definitely can till it isn't as giddy low to mid rpm. When it's rainy and you kick it to see if it'll breakem loose the 87 just isn't as fun. In the winter here 60-80Fish 87 is more viable. Also at 100F+ the 87 idled better below 620rpm, the 93 at 550rpm would load up and miss even at 20:1 AFR. The same engine in a Corvette mostly wouldn't need the 93, but the truck gets driven pretty dang hard no matter how hot it is. The extra $15 is worth it for towing or for fun.

[@JoshuaHowley]

THANK YOU! I have been trying to tell people if you aren't having issues at 87, you're not going to get a boost in power or milage going to a higher octane. Yes, this is biased on just normal everyday engines, not high compression or forced induction.

[@GeoHvl]

I was stationed at a Naval Air Station; the aircraft mechanics mixed AV-Gas with the pump fuel for their muscle cars.

[@christianmayhew2617]

Odd? I was stationed at a Naval Air Station too..........everything ran on JP-4 or JP-5, basically diesel........nobody was mixing squat.

[@kleetus92]

Hope they weren't EFI engines, or they got really good at changing O2 sensors...

[@thatrealcarguy]

My buddy saw a 95hp gain on his supercharged 6th gen Camaro SS. When you add boost E85 really shines!

[@Bacongrease00]

Because you get better intake temperature and can run a lot more timing. Even leaner if you want too since E85 is about 105 octane.

[@abraman5]

I wish they tested nitro 50/50, it could probably one up straight methanol. Supercharged fuel 🧐

[@markbremmer8642]

BOOM!!! Is the answer your seeking.

[@garywaddle7235]

I loved Steve in Coach and wondered what he's been doing since then!

[@dennisglodoski6365]

I would love to see these guys this test on a LH2 North Star engine or even the LC3 North Star engine

[@corvetteZ3r]

Would love love LOVE to see an LC3 on E85. I almost bought an XLR-V to build with modern technology applied

[@Copesthetic-Aesthetic]

Been buying premium same gas station on my way to work, around 64 miles round trip. All highway, always the same MPG. 1 trip would be a 1/4 tank of gas. Got the 87 today and it only used an 1/8 of tank. Now I can only assume so few people buy the premium gas it's most likely old. Where the holding tanks for 87 octane fuel gets fresh fuel more often

[@leftyeh6495]

Nope. It's simply harder to ignite the 91, so it acts like bad 87 right away. If you don't need it, you don't need it. Add compression and ignition timing to the max and then you'll need it.

[@Copesthetic-Aesthetic]

@@leftyeh6495 The car is a 2010 Mazda 3. I was assuming the electronic ignition would advance the timing for the higher octane, it did not. Yet my old 1997 626 had to have 91 minimum or the valves would tick.

[@BuzzLOLOL]

87 gas can have more energy than 91 depending on what additives they use to deaden the 87 down to 91 levels...

[@thyspaine9660]

From my admittedly limited experience, octane doesn’t directly affect power output. It’s purely knock resistance. However, higher octane fuel is better for boosted applications and may even be required once past a certain boost point. So whilst this is a conclusive test, it would be even more informative if you used a second engine that was boosted to highlight what low octane fuel would do cause.

[@jedpratte]

Most Na motors almost always reach MBT before knock. Boosted its a very different story are they are almost always knock limited. High octane fuels or e85 is a must have with boost.

[@thyspaine9660]

@@jedpratte that’s why I run 99 octane in my car 👍

[@deankay4434]

The two problem with E85 is distracted people putting the “Cheap Fuel” in a vehicle not designed to run on it as you will get a dozen codes before the enable criteria stops counting. I am every dealership ship has a special tool for detecting the % of alcohol in the tank or a simple time proven test of letting a sample sit on the bench overnight. Slow, effective and cheap as it separates. I have been ask hundreds of time about this fuel purchasing decision and response is the same. Follow the owners manual, but with knock sensors, mixture ratio feed back and modern PCM controlling everything, only using a top tier fuel will keep injectors clean. Yes, E85 may be 30% cheaper, but you burn 30% more to get the same groceries as last week! DK, ASE master tech since 78

[@thomasvittetoe1930]

I’m sure doing this was a very expensive test to do in California 😂😂😂

[@jhalkoski]

Not when it's the company paying for it

[@Exemplifiera]

I think motor trend can afford it, considering all their sponsored content from manufacturers.

[@BuzzLOLOL]

This was prolly filmed before the PLANDEMIC...

[@baddriversoflittlerock8359]

@@BuzzLOLOL looked like during since they had mask on in the engine room.

[@pbsocal1]

REEEEEEEEEEEE! Thanks Gavin

[@anomamos9095]

In case no one has said it , it’s not the gas making the power (unless it contains higher specific energy) it’s the motor burning that gas under specific conditions that makes the power. A higher octane fuel may actually contain less specific energy (e85) than a lower octane fuel but you can change the conditions it is burnt under to get more power out of it. Ww2 aircraft engines created massive power out of fairly awful fuel by having large displacement multiple cylinders and low compression. As fuel improvements were made they increased compression and boost to get more power out of the same engine. An early Merlin went from about 500 hp to about 2600 hp by the end

[@Punk-Jw]

The thing is though is its just like you said, you can control the atmosphere in the dyno room, an engine compartment is a different story, not only that but you were running it wide open throttle with a controlled load on the engine, a towing application this would be completely different. I feel like you really didnt express that enough...a stock engine also would be different. Not all gasoline is created equal....

[@AH-lw2bj]

Also under boost applications, super or turbo charged, octane is really important My 2018 VW golf shaved 0.5s off it's 1/4 mile time just going from 87 to 93 octane, no tune, completely stock car

[@XC2long4u]

Unless you're running the stock tune. If you run 87 octane, depending on the engine, the ECM will pull timing resulting in less HP. Switch to 91 and you will pick up a few HP because the ECM will bump the timing back up.

[@blkcoupequattro]

Engine cam timing or valve sequencing is fixed, so engine timing is largely a mood point peak hp tq wise. The heads on that engine are pretty good flowing out of the box. It would be interesting to play around with cam timing, and compression ratio's to see were that get us power wise, say 11.5 to 1 ration, or 12 to 1...

[@jonaspoelmans8603]

indeed, the only BIG difference between the octane's is the 'knock' resistance.

[@Mike62501]

In 1974 Dr.Dean Hill and his partner printed the H&H Pocket Dyno. Explaining the gasoline and what the numbers really mean. I will see if I can find mine but I think it said 95 checking. Found it 97.5 octane is all you need to run 14:1-1

[@BuzzLOLOL]

Octane rated differently back then... also rated differently now in Europe...

[@TheBandit7613]

in my classic 351 Cleveland mustang I run ethanol-free 93 octane. I would really like to see this test with ethanol free 100% gas.

[@ddd228]

I drive 30 miles away to buy my E free gasoline. Farm country.

[@corvetteZ3r]

No difference

[@TheBandit7613]

@@corvetteZ3r Ethanol has about 1/2 the BTU's of gasoline. 10% ethanol will yield @5% less hp and fuel economy. It also vaporizes at much lower temps, vapor lock or running lean is very common with ethanol. And it turns out ethanol is a contributor to smog formation. The Sierra Club is now against it's use.

[@TheBandit7613]

@@ddd228 Me too. I bought a 100 gal tank for my pickup.

[@Brock_Landers]

So I have a 1997 Civic coupe with a fully built LSVTEC with a GT3582R turbo and I have talked to many tuners over the years on the advantages of different fuels. My engine in it's current configuration has a set of 9.0:1 CP pistons, standard length Eagle rods, and a stock crank, so it doesn't need anything crazy, but with the turbo I would never run anything less than 93 octane pump gas. My last turbo build was my 2001 Honda Accord with a J32A2 (260 HP stock 10.0:1 compression with stock internals) and with a Garrett GTS3582 turbo on 93 octane pump gas with an AEM 340 LPH fuel pump and some custom made Injector Nation 1000cc injectors it made 502 whp at 10 psi. My Civic runs on E85 now with a rewired and relayed Walbro 530 LPH Hellcat fuel pump and Grams 2200cc injectors and at almost 30 psi it makes 709 whp, and it's still on the same dyno tune (just cleaned up ignition timing) as it was when it made 612 whp at 26 psi. E85 has a higher octane rating (something like 105 octane) than 93 octane pump gas, and it burns much cooler than regular gasoline, so it keeps your engine cooler and allows for more aggressive ignition timing.

[@diesel46809]

Awesome demonstration of the gas difference or little there of. Still waiting for you guy's and UTG to do your motor challenge. I know of course you are ready but I know UTG backed out by not saying anything anymore about it. Great job guy's, it just goes to show how much time you all spend doing the numbers instead of just talking about it. Keep up the great work.

[@TL-angzarr]

Yeah I'd like to see a throw down with UTG too.

[@RedEyedPatriot]

Still rather watch UTG.

[@SophiaAphrodite]

I think the BIG take here is if you run bracket racing you BETTER run the exact same fuel the whole day. Because even those small changes even before the e85 can get you DQ'd . Methanol is not really a reasonable test for normal racing. Otherwise no matter. But this also does mean that crate engines are just so well engineered.

[@davidpepin6443]

Please do a vid with a supercharger and turbo differences in gas! I bet we will see some larger differences for sure.

[@pederlindstrom3132]

Greetings from northen Sweden. This might be a little off topic on race engines.. My car, Volvo S60 T5 that has a BSR 3 chip in it, 350hp and close to 500 Nm torque (368 ft-lb I think) Here we have 95 and 98 octane pump gas. I use 98 octane as it feels smoother and runs better in the cold winter. 95 octane gas 10% E85 mixed in as well.

[@idrift314]

The best octant really depends on your compression ratio… so using a built motor with high compression is a biased test. Do the test on a 4cylinder turbo with 8.5:1 compression, then do a v6 at 9.5:1, and then a motor that’s 11.5:1 I bet you’ll get different results

[@michaelward_GoVentureFab]

In my opinion, this is the best show ever made for fear heads! Hands down!

[@BryanRT326]

Why did the gasoline hp numbers go from 500 to 700 after the methanol test? What am I missing? Is there tests we aren’t seeing?

[@nonyabusinesss3025]

More perfect burning, plus more of it @ 9-1 compared to 14-1 fuel/air. Additionally with that extra octane giving ample room before pre-detonation, you could also add BOOST!

[@CarsandCats]

They merged two tests together.

[@oldblueaccord2629]

What video are you talking about? They never ran Methanol and no motor made 700 hp. You zrussian guys are getting beat bad.

[@mmazz30]

2 different episodes...i thought i was going looney

[@rickboretirementplan]

@@nonyabusinesss3025 The engine went from a LS to a BBC for the last test.

[@ronconrad3507]

In my XK8 4 liter dohc It likes 1 gal of street avail race grade 116 and 93 it runs way better snapper then no blend and keeps the engine lite off (02 sensors) I live in Havasu Az.

[@ranjitsidhu567]

can you guys do this same test with a supercharged engine?

[@thirrteenthirrteen5528]

Very well done. Keep them coming!

[@jedpratte]

Have been playing with e85 for i think 8 years now. Amazing stuff. The stuff we get from the pump here in iowa i have tested up to 89% before but long as its 85%+ i have seen results similar to what i can do with c16 on my small displacement high comp boost stuff. My 10:1 2.0 on a 62mm runs only e85 and sees up to 40psi on it. I would hate to even try to run this motor on pump fuel would not work well at all.

[@sontagfamily5611]

E85 is always cheaper at Casey's as well.

[@albubbles9232]

Are you using California fuel blend? Winter or summer blend? Does the Pump gas ( 87 or 93)have 10% ethanol? We can get “sport gas” 93 w/ no ethanol.

[@lisas7805]

I've never seen this show till today! This episode was so interesting! I love learning just about anything that we can use in daily life. I'm not completely mechanically inclined but I do have an idea. I was wondering about the viscosity of each different fuel used. Would that effect the delivery time and amount for each different fuel through the injectors? I was thinking the AFR adjustment is what fixes that but I didn't catch the explanation if they gave it.

[@rustynail914]

I learned from an old crew chief about 20 years ago, that the lowest octane you can run without pinging, will yield the most power and efficiency. Funny, this video proves the efficiency part.

[@MSK23]

I wonder how much each type of fuel have an affect on the mileage, that would be interesting to watch.

[@corbinschad1]

Not much. My 6.2 silverado tuned for 91 gets about .8 better mpg than tuned for 87. So while I do get better mileage on 91, the dollars per mile is worse. With e85 the fuel mileage is terrible. E85 is cheaper than 87, but not cheap enough to make up the difference in low mpg. So again, the dollars per mile is worse. The only way to increase mpg is with compression. You have to run the max compression that the fuel can handle or you are not utilizing the fuel. Hope that helps.

[@leftyeh6495]

E85 l96, 7800lb truck. I get 14mpg with 87 or 91, and 10mpg with e85. I do use 91 for towing simply because I'll be under a heavy load with high heat creating the biggest chance of detonation. Elevation is 3000'-9000'.

[@trm4life]

So modern cars were designed for ethanol ie: the rubber lines and gaskets and ecu. My car is a 2002, recommends 91 octane but ethanol blended 87 has been around longer than the car. Is it going to hurt it long term to run 10% ethanol 87, or should I keep killing myself dumping 91 into it?

[@trm4life]

Or does my car just fall into that gray area where it's "iffy" to use 87 octane with 10% ethanol? Is it better to use 87 without ethanol? I'm not worried about power, I'm worried about long term damage, since the sticker on the gas door says premium fuel recommended. The owners manual recommends the same. 87 recommended for all other models (I have a Sentra SE-R Spec-v. It has a secondary intake butterfly, much like a dual barrel carb, but on every cylinder)

[@heavenlyblue]

Very interesting - am surprised by the results. Now I do not feel bad putting normal gas in my car the past several decades and saving some money also.

[@MakingStuffUp1]

Could you do a dyno demonstration of Brake Specific Fuel Consumption covering both acceleration and steady state operation.

[@tylerseitz6337]

I've got a question. Does exhaust pipe length and diameter alter the fuel air ratio? How badly is it effected?

[@ChristopherHallett]

How could it? The air/fuel ratio is determined by injector pulse width and fuel system pressure.

[@drakrazerclaw5146]

Exhaust scavenging changes the ratio, as a result of the length, diameter, ect. But the amount varies with each engine.

[@drakrazerclaw5146]

All that determines is the amount of fuel injected...if you scavenge less you will be rich,if you scavenge more you will be lean.

[@SophiaAphrodite]

@@drakrazerclaw5146 Scavenging does not do what you think it does.

[@drakrazerclaw5146]

@@SophiaAphrodite Oh...I only spent 30K plus learning everything about building race engines...but please educate me...

[@jamesray8771]

My 428CJ at 13.1 loves E85 ... can't wait get the track see the difference

[@billballin6948]

Wish they did methanol on that LS as well instead then doing the methanol test on something else.

[@logicalChimp]

Pretty sure they did the Meth test on the same block... they had to change the carb because Meth requires much higher throughput (double the flow, compared to petrol)

[@billballin6948]

@@logicalChimp I don’t think they did. If you compare the numbers from the LS graph to the one of the different engine, the data points are all different as well. The engine they did the methanol run on looks to be a big block of some sort (the valve covers are much taller than an LS). Even if it is the same engine, which it isn’t, now they’re comparing carburetor vs port as well and not keeping variables as limited as possible. This should’ve been two separate videos, e85 vs gasoline on an LS, and then one for whatever engine they used for that methanol pull.

[@jareknowak8712]

I had Mitsubishi, N/A, 12,5:1 compression, direct injection, and i could not run on 95 oct, only on 98. On 95 oct engine gave "check engine" light on the first WOT. Suprised that 87 oct works so well with 10,7:1 compresion engine.

[@olivermolteno7876]

It all depends on combustion chamber design, not all engines are created equal

[@jareknowak8712]

@@olivermolteno7876 Yes, design, AFR and ignition timing.

[@jessemurray1757]

it doesn't, 87 in an LS3 is a very bad idea.

[@oldblueaccord2629]

@@jessemurray1757 They just ran one on it..Now what?

[@THEFERMANATOR]

I'm guessing you're looking at RON octane numbers, we use R+M/2 octane ratings. I believe your 91 is our 87 and your 98 is our 93.

[@johnclary729]

This engine has a good combustion chamber, it doesn't care about octane or spark lead.

[@BuzzLOLOL]

Also has computer/knock sensor...

[@johnclary729]

@@BuzzLOLOL Can't use a knock sensor on the dyno because vibrations from the solid-mounted engine confuse the sensors.

[@BuzzLOLOL]

@@johnclary729 - So they just let the engine be destroyed?

[@johnclary729]

@@BuzzLOLOL No, they start with a low amount of advance, then creep up on it until the engine stops making more power, which happens well before knock.

[@brianbloom1799]

Yes it Matters, If your Motor is 11to1 and up, yes it matters, or it will Ping.Higher the compression The higher octane needed.

[@GTStuning-]

Yup, on 91 octane I was knock limited on a 427 7.0 before reaching optimal spark. I then increased octane to 97 and I made 40 more rwhp without seeing knock.

[@jessemurray1757]

I wonder how many "TOONERS" are going to try running 87 octane with 29 degrees of timing in their LS3 now because of this. The typical LS3 is not going to want that much timing even on 93. Trying to run that much timing on 87 is seriously asking for trouble. If you do, better pray your knock sensors are working properly because its gonna be using them. From my experience the only LS engines that can handle high 20's on 87 octane were the older Gen 3 lower compression engines. It must have something to do with difference between being on the stand vs in the vehicle because this isn't the first time I've seen them claim crazy timing numbers.

[@evoraptor]

Perfect conditions vs. real world, right? They noted in the video, but good luck running lower octanes in a street car for long periods of time at the track, drag racing or road course or wherever.

[@BuzzLOLOL]

29 is low, in 1970's engines needed 38 - 40 degrees to make any power...

[@jessemurray1757]

@@BuzzLOLOL I'm aware but 29 is not low for LS engines.

[@BroBob1254]

Very interesting! Question I have 2 snowmobiles that require "High Test". First sled has a 1000 CC 4 cylinder 4 stroke. 2nd Sled 1000 CC 3 Cylinder 4 stroke Turbo Charged. I'm wondering now if the more expensive High Test is really needed? Thanks!

[@dukenukem7183]

I'm up 2 mpg after switching to non-ethanol pump gas

[@mrmedium7984]

ethanol mix is less energy dense and likes to collect water

[@oldblueaccord2629]

@@mrmedium7984 ...and makes more power.

[@JSparrowist]

I’ve been running my lawn mower on methanol for the passed two years with great success! It doesn’t bog down as much when stressed with tall grass. 🤷‍♂️ It’s a winner for me!

[@MattWybiral]

Thank you for saying the torque units correctly.

[@wireproof]

I would love to see 10% ethanol fuel versus ethanol free

[@ClaudeSac]

Again? The internet is filled with videos like that....

[@bobberttv8565]

Put to use that have a constant ghost knock issue 101 and 109 do absolute wonders