Would definitely like to see Jeremiah make a big HHO generator

from what I've seen, in modern driving techniques, the most popular way to improve fuel efficiency is never stop for red lights

one of the best things you can do ties very well with the "watch how you drive, keep your foot out of it" line is to try to use your brakes as little as possible. obviously there will be times where you have to come to a stop, but there may be plenty of times where you can just let off the gas earlier and coast for longer, letting gravity and friction slow you down instead of braking.

It was super cool when Mythbusters did the hydrogen cell and it did nothing, but then turned around and showed that a regular carbeureted car will absolutely run off of direct hydrogen injection into the carb, at least until it backfired.

I'd like to see Jeremiah do literally anything he wants.

Yes please! Make a hyper-miler!! Also you should power it with Jeramiah's engine. Side-note: Justin's really gotten comfortable and is a lot fun to watch as a presenter now!

The savings with throttle and brake discipline is mind boggling.

That's my "Roadmaster" (Its actually a Caprice Wagon) featured at 11:11. The guy i bought it from built it to hypermile and tow trailers. It has a 5 speed out of a Chevy truck too. It easily gets 30mpg. It can get even better mileage if you keep your foot out of it.

Justin is definitely a great addition to the team, and he's fitting in really well. Great stuff.

I can still remember the Mythbusters episode about the tailgate up/down. Literally one of the most definitive results in the shows entire history.

I have tested the tire thing myself. It 100% increses mpg. "Overinflating" is indeed bad and will likely cost you more, but inflating to the max rated psi on the tire or just slightly below that increased my mpg by about 2mpg. For perspective, i was getting about 13/14mpg in my F150. Now im getting around 16mpg depending on how aggressive i drive. Havent changed anything else.

Actually if you read on each gas pump it says volume corrected to 15 degrees Celsius. Hot or cold the volume of gasoline going in is measured as if it were 15 degrees Celsius outside.

I think a hyper eco modded vehicle with Jeremiah’s hydrogen genny would be an interesting series. Start it in stages like Hi-Low and keep adding to it until you reach peak geek or startling efficiency!

the fact that they still have the "supercharger" on the vw shows dedication

Using cruise controls is a huge way to help increase your MPG.

i would like to see you guys take a guzzler like a hellcat and make it economically viable.. what shape does it turn into? whats the final mpg?? so fun, make it a series if you want..

Dude, Ecomod a small hybrid like a Honda CR-Z and then Ecomod something really uneconomical like a Hellcat to see which you can make a bigger difference on! That would be awesome.

Justin really is a dope new addition to the donut team, love to see him get more comfortable infront of the camera!

damn i would absolutely LOVE to see yall truly try to make a hyper-miler car. ecomodding is wild but i would LOVE to see it work ahah how sick would it be to get a mustang to like 60mpg

I'm not even a car guy, but do love this channel, got my cousin a car guy watching you guys, I think we need to put Jeremiah brain to the test.

Justin did an awesome job hosting this episode. He seems so much more confident. Yet ANOTHER banger from the crew. Keep it up!

The ecomod would be a great series. Myth busters also did an episode where they used a bunch of clay to make a golf ball dimpled car

The windows up thing is actually variable. If you're riding slow, the air resistance will be naturally lower, and thus the impact of the windows being open is much lesser. HOWEVER after a certain speed threshold, the air resistance becomes much higher (the faster you go the more the wind resistance affects you), so having the windows up becomes more fuel efficient

I would absolutely love to see an ecomod im trying to do this to my truck and would lobe to see what you guys go through also!

love to see an eco mod, the cars always end up looking so goofy, i’d love to see how over the top you guys go with the concept

It's so awesome seeing Justin get more confident in front of the camera, he's a great addition so far.

I love Justin, he has great presence and personality, and is a joy to watch! :)

Justin did a great job this episode. Please have him hosting more!

I really loved this dynamic between them two lmao. Justin ripping up the windshield wipers as if it owed him money was hilarious.

On the automatic vs manual. Manuals usually weigh less (sometimes by a lot). That can make a difference.

Depending on your car, your engine size/power, and alternator draw….the whole electrical stuff using more fuel can actually be big. Anyone who owns an older gem Honda Fit knows that if you have your lights and radio on, and try to roll up or down 2 windows at the same time, it feels like you lose about 30% power lol. Also, I think the manual transmission thing is because you can neutral and coast. I used to hypermile in my 02 Saturn sc2 by neutraling whenever I could and would get 80 mpg plus

Using cruise control helped me the most. Leave early and just cruise the speed limit

DEFINITELY do some sort of eco modding series! That'd be a great watch guys!

Lol yah the point at the end I think is the most valid. There are a ton of things that can VERY slightly change your MPG. But the biggest one is your own foot.

I LOVE that Cabrio❤️ the most fun project car I’ve ever had was one of those I got from a junkyard🥰

Would love to see an Ecomod or Aeromod car build! Could even have two cars and teams to compete with each other and see who can make the craziest and most efficient car!

For the obd2 fix, someone that actually knows how computers works, went through the "micro chip" and found ALL it did was blink the leds. Only 2 of the prongs actually had power going to them. One positive, one ground

The gas pump thing also is corrected to a temperature, 15 degrees Celsius in Canada. Also I believe the myth busters segment shows you can be quite far back from a semi and still have a measure able gain to mpg.

Yes I would like to see all the videos that you guys described in this video. Keep up the great work. I don't believe that running the AC does not use as much fuel as having my windows down. I lose power in my 2005 Mustang when running the AC.

I’m glad Justin’s taking a bigger role in videos, I really like him as the new guy

Yes! I'd love to see the Donut crew take on an eco mod, and 100% should be a stupid inefficient car like a hellcat or something. Would be hilarious and fun to watch

One clarification you should make is that “Top Tier” is not to be confused with higher octane, top tier gas is gas that has additives across all octane grades, gas stations without the top tier sticker at the pumps usually means that is just plain gas without the additives.

My all time record for MPG in my 2017 Miata RF Club manual with a full tank was 43. Something MPG. But I was coasting when I could and driving 55-60MPH on the freeway. This is with 77k miles driven on engine with 87octane.

Regarding "windows down", mythbusters also tested this one not once, but twice. While windows up will always be better, if you need cooling AC is NOT always more efficient. Below 50 mph, windows down is more efficient than running AC, and above 50mph, AC is more efficient.

Not even lie. Sometimes I watch old donut videos to make me laugh or to cheer me up because when I was homeless and living couch to couch this is really the only thing besides making music that entertained me while going through those struggles. To this day it still brings me happiness to watch the new shit you guys are posting. Please keep at it !

I have to use higher octane, for detonation. Never thought I'd get better mileage, so I'm glad I educated myself. Good job guys

Agree with the ldv tailgate. But what we have experienced was a trailer we had hooked behind a car. Was huge difference in performance and fuel consumption.

i would most definitely want to see an eco modded car, that sounds very interesting, especially if you can get gas mileage over 50 at least, that’d be super cool to see. I also would love to see jerry make a hydrogen powered generator for a car

Props to Justin for getting into hosting his own segments and videos now. Great addition to Donut 💪

XD I used to love manuals for snow driving. in the 90's I felt like I had a ton more control in the snow when I could shift, but as tech got better... the advantage vanished

So I did the test, driving behind a semi for 30 miles. My MPG went from 27 to 41 MPG ! This for 2 reasons : - resistance of air highly reduces - the semi force you to keep a steady and limited speed Anyway, I will do it more often now, hope to not kill myself in the process.

When I was a kid I used to tailgate tractor trailers on long drives and the difference was astonishing. I could use about half the throttle I was using before I starting drafting off of the truck. You gotta be like dangerously close though. Terrible idea but hey, it was for science.

Love to see a hydrogen fuel cell build with Jeremiah and an eco mod build with Nolan. A face-off to see who achieves the best fuel economy.

Slush box autos in the past used more fuel since they designed for smooth transitions. They also usually had three (four with overdrive) gears making them less efficient. Newer dual clutch transmissions have between 7 to 10 gears allowing for very efficient gear ratios

As a long time Prius driver, the biggest differences in MPG I've seen comes from 1. Good driving technique (rapid acceleration and deceleration kill fuel economy) 2. Make sure tires are properly inflated. Underinflated tires lower fuel economy substantially 3. Weather (not really something you can control) with hybrid vehicles the drive battery is adversely affected by extremes in temperature. On really hot or really cold days my MPG can drop as much as 8MPG. 4. Drafting actually works well on the highway but you don't have to drive as close to large vehicles as you think. Just keeping a safe 3 second distance from large trucks improves economy over following smaller vehicles.

Tailgating a semi works. When I was a terminal manager for a trucking company, I had to head from Atlanta to Florida for a trip. I coordinated with one of my drivers and tailgated his trailer while in a Prius and got 89 mpg on my first tank.

Good to see that Justin got in the groove and got his confidence up! Now he is matching the energy level of the entire crew. Good for you Justin!

Really cool to see Justin come into his own and take the lead on this video!! Was skeptical about how much I liked him compared to the other guys, cause yall are all so awesome! But after this one I love seeing his personality and what he has to offer! Cheers guys, thanks for another great video!

Interesting summary. Thank you for the content.

Absolutely do an eco mod. My stepdad traded his 96 GMC Suburban for a 96 Geo Metro during the Great Recession and we loved that car. He loved it so much he bought a second one. A 1991 4door automatic.

No matter what hack you use, at the end of the day, Clarkson said it best: "It's not WHAT you drive, it's HOW you drive"

I would love to see an eco themed high low. Even if it's not one where you make two eco cars you can still have fun in.

110% yes to you guys building a hypermiling rig!

A major contributor to auto versus manual fuel savings was the torque converter slip. Modern vehicles will use a locking torque converter or dual-clutch to prevent that power-loss, thus increasing efficiency. That wasn't super prominent though until about a decade ago, not so much 50 years ago. The more you know!

I love that Justin is finally hosting he should get his own show he became an instant fan favorite

Definitely wanna see the eco mods on a crazy car! And can only imagine what Jeremiah could build would love to see both! ! You guys rock watch you every night keep the good content coming!!!

Would love to see an Eco or Aero mod build! love your content and have recently experienced the Donut Media Forza cameo. Keeep it up guys!

Holy crap the By Release music had me double checking what video I was on A runescape reference on a video about scams is super fitting

I'd love to see an ecomodded 80s or 90s brick pickup like an F150. I know the hypermiler guys have used rangers before but one of those 12mpg V8 bricks would be amazing to see the benefits on.

Finally, Justin does his own episode. So cool to see this. And he seems more comfortable in front of the camera.

Always love when Justin goes Hulk mode and rips things apart!

My question is, what is the most fuel efficient speed? Like the faster you go the more distance you travel but you also burn more gas. I’m sure it’s different for every vehicle, but I’m curious what speed optimizes gas and distance.

I like how you bust all these myths based on how you feel rather than actually testing them. Science 👍🏻

The best trick would be driving slower. At higher speeds most of the engine power is used to overcome air resistance, which rises exponentially. Double the speed means quadruple the air resistance

They say by filling up as slow as the pump will allow, more ends up in your tank. When the gasoline flows faster, more evaporates, and is recollected into a special outlet tube that's inside the nozzle.

Correction, if it says 87 you don't HAVE to use 87, but you're not getting any benefit. In SOME cars marked 91 you CAN use lower octane without damaging your engine, BUT it will have a catastrophic effect on your mileage. Which means more money in the long run, even if it doesn't actually damage anything. As for windows vs. A/C depends on how fast you're going. Around town, windows down is cheaper. On the highway, A/C is better for mileage.

Expectations: "Testing fuel economy hacks" Reality: *no testing was actually done*

Yes to the Eco mod and yes to the HHO mod. I love seeing you guys build awesome things!

Didn't think about different gears for efficiency (probably because I'm not old enough to have experience with lots of older cars with manual transmissions), but I believe that a lot of older cars were a lot lighter because of building material/design choices that aren't acceptable anymore due to crash safety, and reduced weight would improve efficiency.

I love how descriptive the captions are as someone who has a hard time hearing the captions are truly a godsend

theres a few mistakes here and there. overinflating your tires by around 10% doesnt create uneven wear and also doesnt ruin your handling, but will do a tiny bit of fuel saving. just dont overdo it. better gas -> here in germany we have 5% ethanol and 10% ethanol gas. the price is so close that calculation wise it doesnt make any difference, but my dad uses around 5% more fuel with it being only 2% cheaper. i dont recommend the 10% based on that. cold and hot gas at a gas station -> of course the tanks also heat up a bit. every gas station that i worked on could check the temp of the stored fuel at any given time, and in summer the fuel actually had a temp difference from night to day. 40°F during the night and up to 52°F during the day. but the pumps are actually programmed to take that into account while selling. here in germany they are calculated to measure what volume the fuel would have at 68°F and they account for it being colder and thus taking up less volume removing side mirrors -> mercedes measured during the 80's or 90's that removing both sidemirrors would actually decrease aerodynamic drag by around 15%, which is ginormous. thats also why most new semi-trucks here in europe actually have side cameras instead of mirrors. modern mirrors most likely cause a bit less drag than what merc measured back when they did, but still you shouldnt remove your mirrors for safety and legality reasons. also cars without mirrors look weird. auxilleries -> AC is a very big one, which can dependign on your model take up to 5% of your total cars power, especially in economy cars. but lights for example were measured by volvo -> they couldnt measure the difference between regular light on and off on their testing track. keep your lights on guys. if you have a biiiiig aftermarket stereo tho, keep it down, that will eat energy and with that fuel. and now the big one; transmission -> most cars and/or most drivers will drive more efficient with an automatic. you cant be as precise or as quick as an automatic gearbox, even if youre a racedriver. they banned automatics and cvt's from f1 for a reason. but, and thats a very small but -> if you have an econobox and you know the speeds you need, and the gears line up with your needed speeds, and you are very very good, quick and consistent with your manual gearbox you might safe a miniscule amount of fuel as manuals are mechanically more efficient in transmitting the power and are generally lighter. this all falls apart the moment you do anything outside of these gear ranges or even start to drive more sporty with a lot of gearchanges. but rolling on the highway with a fixed speed the manual can be more efficient. thats the case maybe 2% of the time. works for my dad with his driving style and commute, doesnt work for my mom with her driving style. sooo there is a tiny spec of truth even today. but if you go for efficiency in all situation a CVT is actually the best, as much as it hurts us car guys.

I've been a long time donut fan and just this week I got my license and my grandmas old Cadillac. Can't wait to apply everything I've learned from you guys. Thanks.

Love this channel! Miss you videos. E46 guy here & I would Love to see e46 stuff. Make a drift car lol I bet it would be a monster!

the window up vs down thing also depends on the speed you are going. at 40 mph winds down is more efficient for personal cooling. over 40 AC is more efficient ( due to drag).

Please do more with Justin! You’re such a natural addition to the team. It’s like you’ve been there since the beginning. Keep it up boys!

I would love to see you guys do an eco mod version of a truck, making it egg shaped but still a practical vehicle for hauling 4x8s and bags of fertilizer.

Testing hacks without actual tests- this is a new level of science!)

the wiper thing ignores that in alot of cars the resting position of the wiper is below the top of the hood panel, and even when it isn't it's tucked right down into that nook where it minimises the tiny effect it might have, they're generally designed to sit somewhere the wind isn't gonna pick em up.

I'd love to see you guys mod a gas guzzlers into a hyper miling machine

Used to slipstream semis in my 71 VW Bus on road-trips. Helped immensely with engine load and fuel mileage

I'd like to hear more about AC vs windows. AC increases load on the engine, and windows open increases drag, but I've heard below around 45mph, its more efficient to have windows open. I also increased 1-2mpg just this past week by turning the AC up a few degrees.

I would love to see a full tank drive with a/c on vs a/c off in terms of available power and fuel economy

10:44 Adding to the talk: running the AC is more efficient if you plan on driving consistently above 40mph. In the city, window down doesn't affect fuel efficiency that much because the car is rarely fast enough for the aerodynamic drag to be so strong, so this tip is mostly for people who use highways for travel or work.

Shoutout my guy Justin. You can tell he’s getting more comfortable with the squad and the camera! Also I like how the Donut cast helps bring each other up. Big respect to that. These guys are already automotive content legends in the culture!!!

The only thing that actually improved my MPG was easy acceleration, anticipating stops, and cruising at or below the speed limit. Additionally run a eco focused tire vs a grippy summer or blocky snow tire. Weight reduction is cool but I enjoy the comfort features of my vehicle over a 1-2 mpg gain.

You are correct that Mythbuster found the maximum increase very close to the truck, however they also got a 10% increase in MPG at 100 feet, a reasonable following distance at highway speeds.

I would love to see the ENTIRE process of Jeremiah making an HHO generator 😂😂

I formerly wrote vehicle tracking software that measured your fuel efficiency based on 6D motion detection (for a fuel company who were going to award bonus discounts to efficient drivers). 95% of the penalty (as calculated by our mathematicians from experiments) came from brake usage. Maximum fuel efficiency for your vehicle below the speed limit (drag negligible, no excess acceleration i.e. wheelspin) is achieved by allowing yourself time to stop.

Great content as always. Had a heart attack seeing your gas prices =b i forgot where you guys are located for a little.

A lot of factory spoilers are for efficiency. They create a clean separation edge, and a bit of kamm tail.