Gasoline Vs Diesel - 4 Major Differences 

+FourTwenny THUMBS UP . FULLY AGREE. THIS IS WHAT THE INTERNET SUPPOSED TO BE FOR. SHARING KNOWLEDGE.

+COMMENT I love the sharing and Mr. Engineer's explanations are a joy to watch.

+bigstuffeluffaguss ? ? ?

Gweedo Murray He is being satirical. I cracked a smile at his comment to be honest. I agree with you on the explanations on this youtube channel. I have been subbed for like 2 years now. Hands down my favorite channel. I love how simple and straight forward it all is. I am no great mind, but i leave these videos with some understanding, every single time.

+FourTwenny Or sarcastic ? :-) Around these parts, where "it's legal", that "FourTwenny" has a significant meaning. I follow "Eric The Car Guy" too !

No youtube at your youth though.

Palraja Pal hope you see this, stfu 👍🏼

+Kristian's Battletech Channel thanks!

you got it a bit wrong there, the amount of "air poisoned" is not a function of A/F ratio but 1) fuel type 2) fuel amount 3) combustion quality

I'm not saying this is not polluting the planet, you're right there but you're wrong assuming the A/F ratio has something to do with the amount poisoned. The general used unit when talking about pollution is "ppm" aka parts per million which is a concentration, which (multiplied with a constant) can be measured as a mass or mass fraction. See 2) fuel amount, I mentioned. Greenhouse effect differs from generated exhausts, CO is more harmful than CO2, CH4 is more harmful than CO2, SO2 is more harmful than CO2, etc. If fuel is not burned completely like CO or CH4 the combustion quality is lacking. See 3) combustion quality If SO2 is formed the fuel type contains sulfur. See 1) fuel type

I know what air/fuel ratio means and you repeated very nicely what I said. There still is no correlation between "air/fuel ratio" and "toxic gases produced". So when one engine has an A/F ratio of 100000 and does 900mpg and another engine has an A/F ratio of 10 and does 0.1mpg what engine is worse?

"if you introduce 5 times the amount of air with each gallon of fuel - you've poisoned 5 times as much air- pretty basic ." This is not how this works as I already explained several times. You can advertise your own channel spreading your own misinformation seven more times but that does not make it true. If you drill a hole in your exhaust and blow some clean air into the exhaust gast, do you pollute more air? If you say yes explain to me where you can inject clean air into the exhaust gases without producing more poisoned gas. If you say no you're right and should think a little further and tell me where the difference between injecting more air than needed before or after injecting it into the cylinder is. Again I am not saying the technology used today is clean or perfect I am just trying to educate. FYI todays diesel engines have such a high A/F ratio because exhaust gas is recirculated to lower the temperature to reduce NOx emissions.

+David Fisher Haven't yet finished dyno testing, but it's looking more like 175+ HP to me.

+Engineering Explained Could be a good video for April fools.

My God he did it

Four years later he did it

Lmao

+Danny Contreras Cant like this one enough

Cars roll..... but why???

@Lil' Red GTO damn right!

Seth Spurlock and then that music comes in

+kingdavewoody lol

+kingdavewoody BOTH HAVE SMALL PISTONS

+COMMENT W

Diesel lives a quarter mile at a time

kingdavewoody omg dude you had me dying for 2 minutes straiggt bahahahahaha

+Alpha Anderson Thank you!!

+Engineering Explained what makes air hot to ignate air/fuel mixture in diesel engines? and what is use of intercooler to cool air if you need hot air to ignite?

+simeunovicm When the air is compressed it gets hotter. And I think intercoolers are only used for Gasoline engines. Although, I may be wrong, because intercoolers are made to make air colder. So colder air is less dense, so when air is less dense it means you can get more air into the engine.

+simeunovicm Intake gases are heated by being compressed. In forced induction engines, this phenomenon of fluid mechanics happens twice - first by the turbocharger or supercharger, then again inside the cylinder. The purpose of an intercooler is to increase the amount of oxygen taken into the cylinder by cooling the air that was heated as it was compressed by the turbocharger or supercharger. Then, once the air is drawn into the cylinder, it is again heated by compression when the piston comes up to squeeze all the air that is in the cylinder up into the combustion chamber.

+simeunovicm Intake gases are heated by being compressed. In forced induction engines, this phenomenon of fluid mechanics happens twice - first by the turbocharger or supercharger, then again inside the cylinder. The purpose of an intercooler is to increase the amount of oxygen taken into the cylinder by cooling the air that was heated as it was compressed by the turbocharger or supercharger. Then, once the air is drawn into the cylinder, it is again heated by compression when the piston comes up to squeeze all the air that is in the cylinder up into the combustion chamber.

That turbo whistle!

Salim Saif whats that?

I like both engines as an application, but there is something about high rpm that always gets u, u know? Seat on a cbr1000rr (just an example) and tell me im wrong. Also see amg/corevette/porsche/mustang sounds out there just nasty... Maybe the exhaust helps of course...

One time i revved third gear (again cbr) to a personal record. I felt on drugs from adrenaline. I wasn't even going fast. Your body have to involve its weight to fight the acceleration. Diesel is fun on heavy pulls, where you feel like you are about to move a house if it's in your way. (I drove tanks in military and i am talking in the most literal sense of moving a house, even through the house it doesn't stop, and the engines are not that big, on of the puma's, very small tank, it's either GM or dodge 5.7 v8, but the torque. mmmmaaaaannnn..)

When I was really little in the early 80's my mom had a N/A diesel GM car, some Oldsmobile I think it was, or possibly a Chevy. It was a massive turd.

+alter Herr Entspannt Happy to hear it, thanks for watching!

but it is completely wrong. the vacuum being pulled in the gasoline engine moves the piston up again with almost the same force, that the piston needed to pull it in the first place. engine brake in a gasoline engine has nothing to do with a closed butterfly valve. in fact, the gasoline engine has a lower braking power when the butterfly is closed as when it would stay open. the brake effect occurs solely because there are friction losses!

😂😂😂😂

Haha very true

if you look above you might see the reason for the comment... not sure why my comments seem so out of order.. but they seem very much out of place.. my apologies.. no disrespect meant if you read my other above comments.

nah that couldn't possibly be it.. this isn't like the internet or anything... hehe

on a side note.. Quest Remnants of Chaos check it out if you want to... work in progress.. only if you like games.

+Jay Davidson Awesome! By the time I got there most classes were moving out of Broughton (graduated '12). I took statics there, maybe one more. Everything else was EB3, where I lived my last 3 semesters haha.

who is more prone to overheating, gas or diesel? i am torn between the Toyota Prado gas or Prado diesel.

I bought my first diesel about a month ago, an AWD Chevy Equinox. So far I'm seeing around 35+ MPG around the city and 50+ MPG on the highway. Very impressive! And I like the muted diesel "bus engine" sound.

+Des Herbert Happy to hear it, thanks for watching!

+Engineering Explained 39b engine

+Akshay Powale what?

+Liam Jonigan-McGar A 3.9l 6-rotor

+Linda Haugh what about it?

Nope :)

+jonnyroy He's talked about them I believe once before. Search his channel for the videos. I believe they were made either early 2015 or late 2014. But yes, he's made a video on them previously.

Correct. Mazda brand it as skyactive but it's basically very close to a Diesel engine

+Andrew Somerville the Otto cycle is the cycle used by traditional gasoline engines. diesel engines use the more efficient diesel cycle, though you are correct that many modern engines are starting to blur the line between these two cycles.

great topic

+amcheung10 you mean Oil catch cans??

+Maveric James Ching or piston rings?

+paviaaPS3 piston rings don't deserve a whole video. they seal the combustion chamber

what are they made of, how many, hardness, when to replace, ect. he can esely spent 5 min on this subject...

Or whale oil

think you have a point... we need to build whale oil burning engines!

+Philippe Anglade yes.

+Philippe Anglade I have a few, search my channel for "compression ratio" as well as "thermal efficiency." :)

+Engineering Explained Thanks, I just watched them ;) . But I was more thinking of question that could be interresting for petrolheads willing to change their compression ratio. Will the engine produce more torque ? Will it move the torque curve higher in rpms ? Will there be a loss of torque at some rpm ? How may it affect idle ? I know the answers, I'm just thinking it might be a good video idea ;)

+Engineering Explained This is completely unrelated but is it possible for a manual to have remote start?

+Daniel Gamboa Urosa I have had many vehicles with remote start that were manual. You just have to make sure that when you leave your car parked that it's in neutral. Most aftermarket remote start kits have a safety switch that won't even let the car try to start while it's in gear.

+theoldrsftw Historically nitro remote control car engines were 2-cycle engines, though there are 4-cycle engines in that class now. They basically function the same as a larger 2-cycle or 4-cycle gasoline engine, except that instead of an ignition system that provides power to a spark plug to ignite the fuel-air mixture, they use a glow plug. The glow plug is first pre-heated by a battery and is then re-heated each time the engine ignites.

+prairie wanderer interesting. what is better nitro or gas?

theoldrsftw It depends upon the application and nitro is a lot more expensive.

Thank you :)

aeperformance48 I just asked a question...

you're not allowed I'm your boss

+aeperformance48 Good luck with that

+Venator Mortis Cummins. Because I have seen them modified and used in way-more-than-designed-for situations and live through. And they also make engines for real trucks (or semi's) and even those can be turbo'd to insane amounts of strain and still live to tell. My current realistic dream car is a Ram 2500 6.7 I-6 Cummins AWD 4-door and then to gradually over the years tune it up safely to Motortrend Truck Challenge Top 10 numbers but keep it street-legal and still moderately economical for road use. Lavon Miller showed us it can be done. I would be happy with 80-85% of what he has today.

Venator Mortis Im your boss I own you, get used to it kid

+Exia2004 since diesels have a higher compression ratio, the crankshaft is bigger than one in a gas engine. this affects the torque ratios giving the diesel more torque

+Exia2004 Torque talk. Torque and power have a fixed relationship, torque x rpm = power. (to be precise Torque (lb.in) x Speed (RPM) / 63,025) = Power (HP) Look at it this way: torque is about how big a bang you make in the combustion chamber, power is about how soon you can make another bang. So, at the same rpm, such as when starting from a standstill, a diesel can apply more power to the wheels, and gets away faster than a comparable petrol engined car. Yes, it has more torque than the petrol engine, but that means that it is producing more power *at that rpm* The downside for the diesel is that you have to change gear earlier, as a diesels power output drops off sharply after about 4000 rpm, for reasons to do with the way combustion works in the diesel cycle. Now, a word about "rated power". Manufacturers will quote their engine power, say, 140 BHP - this is the maximum power the engine is designed to produce within normal operating parameters. In petrol engines this is frequently reached at 7000 rpm or more, wheras for the diesel it is usually about 4000 or a bit less. If you restricted a petrol engine to the same rev range as a diesel of the same rated power, the petrol engine would never catch up with the diesel. To put it another way, from a standing start, the diesel is *always* producing more power, because it is producing more torque.

diesel is better for the environment and gets so much better fuel mileage. i have a friend who's father has a vw tdi, he gets like 43mpg highway

Ricardo Lupian petrol is getting better and will catch up on diesel in motorway (highway) fuel economy but if your working in mostly city based then just no point with diesel. I had constant DPF issues with my BMW. I drove it 50 miles to start getting it regenerating but kept coming back . Petrol is over all better in my view.

i'll tell ya when mazda comes out with their skyactiv diesel, i will be so excited. it is available in other countries but not the U.S. i'll tell ya clean diesels like the vw tdi. will not have any DPF

Ricardo Lupian every diesel car had to have a DPF installed by law in Europe

my friends dad has a 2013 vw tdi his doesn't have any of that stuff. but a lot of the bigger trucks like f250's have DPF.

When you compress air it gets hot. If you compress it enough, it will get hot enough to ignite fuel. Diesels just compress the air a lot, then fuel is injected and it just burns in the hot air.

I understand that but where is the energy to ignite it taken from? If the pistons are in stillstand yet and you wanna start the engine.. How's that happening?

Oh, engines always have an external starting mechanism. Automobiles and trucks have electric motors bolted to the engines that are used for starting the engine. The electric motor is powered by one or more batteries. The energy needed for compressing the air and injecting the fuel to start the engine comes from the battery. Once the engine is started and running, the alternator on the engine does the work of recharging the battery.

Thank you mate!

each engine got something called motor started to "spin" the crank + diesel engines have glow plugs which are warming up the mixture before start

+Collin Mckernan it is running with seriously excess air, so it is lean enough. So lean that gasoline engines would not even really run with. Also when you have high load, diesel is running richer. With low load it is lean, then amount of heat is limited. Of course slow burning of diesel fuel helps. (diesel burns much like wood, not violently and fast like gasoline)

+Karjis I was going to ask that same question. Great explanation. The example of burning like wood helps to make sense of it too!

+Collin Mckernan With gasoline engines, the gasoline which enters the cylinders is not completely vaporized. Much of it enters the cylinders in droplet form. The vaporization of the gasoline in the cylinders has a significant cooling effect. For that reason, air cooled aviation engines, during take off when full power is required, run on an extra rich mixture so the vaporization of the gasoline keeps the engines from overheating. Of course that is inefficient but durability is more important at that point. Not all gasoline engines will overheat on a lean mixture, but the free O2 resulting from a lean mixture can burn valves. Engines running on a gaseous fuel, such as propane or natural gas, do not get any cooling effect from the evaporation of the fuel and therefore tend to run hotter. As a result they often use better materials for the valves to prevent valve burning. Diesel engines generally have excess air so they tend to run cooler. Also there are slightly more efficient which means that less heat has to be removed.

diesel for torque and efficency, gasoline for high rev/power

actually depending on how much money you have to put into a diesel it can be for speed, torque, and hp, and mpg, but you cant have mpg with the others focused on at the same thing

Gasoline for power?How many petrol engine HGVs do you see?What engine did Audi win several Le Mans races with recently?

Higher fuel efficiency, more torque, and less hazardous handling due to lower combustibility than gasolene. For use in heavy truck applications as well as industrial electric power generators. From your car to your truck to your tractor, to your multimillion dollar oil rig; cleaner, safer, more efficient.

Torque isn't a function of RPM. Horsepower is calculated based on torque and RPM but peak torque isn't always highest in the lower RPMs. When you look at these low displacement N/A gas engine builds that are making big horsepower, the peak torque often isn't that much greater than it is in their stock form. However the curve will look different because the cam profiles, intake manifold/runners and head porting are optimized to make that torque higher in the rev range. Same torque at higher RPM = higher horsepower. Peak torque of an engine can be as high or low as they wanted it to be. This is why VVT is so great for drivability on higher powered low-displacement cars; it allows you to have good torque in the low/mid-range when it's on one cam profile but then when it crosses over into the second cam profile, that one is more optimized to make torque at higher RPMs. It depends entirely on how the people designing the engine want it to function.

cuz he couldn't find one broken down. lol

Gas is short for gasoline, it is not a gas

Thomas Brekke ah :D

+Rokas Getautas Americans refer to petrol as gasoline. GAS is short for gasoline.

+Rokas Getautas Yeah, we American's can't be bothered saying more than one or two syllables of longer words. It's kinda our thing. Sorry bout that, bro.

+COMMENT Benzine or naft here

+DonziGT230 nope, compression in gasoline engines does not cause much engine braking. Why? Because all that energy goes right back into pushing the piston down after the compression stroke, very little is lost as heat and thus the vehicle doesn't slow much. I'm sure wiki will go back and fix your mistake, they're generally pretty good.

I have a stock '88 Ford 7.3 diesel with no braking parts added, open intake and exhaust, and it has more engine braking power than any gas motor I've ever driven due to it's high compression. I've also tested the theory on gas motors by turning the key off and pressing the throttle wide open, no change in braking effort at all with cars, bikes, or trucks. I'll put it out to you or anyone else who wants to feel the truth first hand. Take any traditional gas motor vehicle with a cable operated throttle and EFI, don't wanna do it with a carbureted engine as you'll be pumping raw fuel through the motor and can cause damage. Get going down a hill, turn the key off and move the throttle pedal; you'll find no change in braking effort. If the vacuum theory is true you'll loose all of the 'vacuum braking' when the throttle is opened and you'll find that it doesn't.

Having higher or lower compression does not change the braking effect in a gasoline or diesel engine. GM and Dodge both produce gasoline engines that close off valves to half the cylinders to conserve fuel. This creates an air spring in each cylinder, the force required to compress the air in the up stroke is given back to the crank in the down stroke. A diesel engine that is turning without injecting any fuel is a big air pump. All the braking resistance is due to pumping air through the engine and out the exhaust pipe. If throttle valves have not been added to the intake, no vacuum resistance will be there to add additional resistance to the engine. A real Jake Brake adds braking by interrupting the air spring and wasting that compression stroke out the exhaust. Jake's make a lot of noise because the escaping compressed gas goes supersonic when expanding past the exhaust valve. The smaller the valve opening, the louder the Jake. Exhaust valve brakes just shut off the exhaust pipe and cause the engine to build pressure in the exhaust manifold. Not as noisy, they just hiss. The lack of vacuum is a big bonus for a diesel engine. Very worn gas engines will pull oil down the valve guides and up through the cylinder rings during high vacuum. Worn out diesels don't have this problem. However, diesel vehicles that use vacuum accessories (like vacuum assist brakes) require an additional belt driven vacuum pump. I worked my way through college driving light to medium trucks for a lumber yard. We had several 84-87 Ford diesel one tons with stick shift transmissions. They had almost no engine braking when going down steep hills. We also used 30,000# GVWR "2-tons" with 18' flat dump beds. Most ran gas engines, but mine had a Detroit Diesel Turbo. The diesel had a lot more power, got 10mpg on long runs, but had poor engine braking. The gasser's all had better engine braking. We had a cab-over Peterbuilt with a Cummins and a Jake brake, I only drove it a couple of times and I never did so without the Jake turned on. The Jake was very effective. We also ran a Ford 10 wheeler with Caterpillar V8. It had a hissing exhaust brake. Definitely not as good as the Jake. When it was loaded, if I turned off it's exhaust brake and let off the accelerator pedal, it was just like being in neutral and coasting, no brake effect at all.

Now, about your 88. I believe it is possible for a diesel to develop more engine braking as the engine wears out. When not pressing the accelerator, thus not adding fuel to the engine. The up stroke would "attempt to" compress the air to about 20-1. Air that is lost out of leaky valves and past worn piston rings would not be there to aid in pushing the piston back on the down stroke. Therefore, it might be possible for a well worn diesel to have a kind of Jake Brake effect just due to the worn out condition of the motor.

The compression on it is good except for one cylinder that's a bit low. I've driven dozens of these from back when they were new and they all had about the same braking effect. Try my key off throttle open test on a gas motor and you'll see that it's not the vacuum that creates braking. I've driven many medium to heavy duty gas and diesel trucks and my experience with their engine braking is completely different than yours.

+Armesis P why not??

max19970 They are slow, even when turbocharged and stage 1 tuned, produce a ton of smoke even when properly maintained, unreliable and noisy. The worst part is the turbo lag. The only thing good about it was that it was economical, but only a person on pension would worry about that. My turbo diesel car used an italian engine btw, bloody awful

+Armesis P although alfa romeo's jtd 2.0 liter tdiesel is a one of a kind, used im the 156, and i could give you more examples of top of the line italian diesels. I think you just had a really bad experience with that car, but you shouldnt let that mold your whole idea on diesels. Diesels nowadys have none the issues they used to, with turbo lag being almost unexistant, and noise and roughness being correctly balanced out plus the great efficience that diesels carry in their dna i think there hasn't been ever a better moment to invest in one

+Armesis P I can absolutely guarantee you my 7.3 Powerstroke diesel will generate far more torque and HP than its 460 Gas counterpart. Since modern injection systems came about (HUEI and Common Rail) staring in the mid ninties, the diesel has been king in light trucks and SUV's. The gas trucks just can't keep up. As a person who tows extensively, I would always choose a diesel over a gas motor. Its not just me, I've never seen heavy haulers use gas motors. Not only do they lack the power they generally require more service intervals don't last the 300,000-900,000 miles I expect for a truck.

+bosborn1 YOu have a big ass turbo and a 7.3 l motor. Youre comparing against a smaller displacement non turbo application. Not really a good comparison but I do agree diesel is almost always goign to be better for towing applications.

Thanks!