Why Do Diesels Get Better MPG? Why Are Diesels More Fuel Efficient?
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- čas přidán 9. 12. 2016
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It seems like common knowledge that Diesel engines get better fuel economy, mileage, or MPG (miles per gallon) than gas engines, but why? This video describes the differences between the engines and the fuel itself. AdeptApe@yahoo.com on Paypal for donations to the channel and thank you. - Auta a dopravní prostředky
This guy really knows his stuff, good work.
Yes he is very good
Bless your heart and others like ya! I really appreciate folks like you sharing their knowledge. Keep up the good work young fella!
FM
Owning a ram 3500 6.7l diesel, I have been hooked on your knowledge. Keep up the great work! You even taught me about my exaust brake and other things the dealership is clueless about.
Really comprehensive and informative. Thank you for letting the rest of us learn from your talents and knowledge. Great video!
Great videos! Where where you 22 years ago when I was a young apprentice! Keep up the great work!
+M Rowsell Well elementary school is where I was! Thanks.
Adept Ape 1 gal of gas has 31000 kcal not cal ....😇
If you live in the US, the term "calories" generally implies kcal. Even our food just says "calorie", unlike most everywhere else in the world that uses joules or kcal as the measurement
Great video on the difference between gas and Diesel engines. Short and sweet and right to the point.Love the engineers facts.Bravo.
Another fine video to watch. Keep them coming.
Adept Ape, Our Diesel Messiah ! 😁👍
Seriously, great work as usual. You deserve every view, thumb up and subscriber you get. 😎
+JIGA BACHI Thank you. My first animation too, although pretty low budget.
Great video again adept!
Great video, thanks for sharing your knowledge.
Your vids are awesome! I'm just getting to know a new Cummins I6 and have been basking in the warmth of diesel fired badassery. Your Cat vids and this help me soak in what that motor really is.
+David Roberts Cummins makes a great engine, I've been itching to start learning about them.
Love It!!!!! what an excellent explanation!
Excellent video. I learned what I needed to.
Doc told me to up my calories so now I know what I'm gonna do...
nice simply explained video. thanks
Old video, but good. I had an 82’ Chevy LUV with a 4 cylinder Isuzu diesel. Got over 40 mpg with that thing. The good ole days
Clear and concise, thank you.
Another great video AA. I think we all can thank Dr. Rudolf Diesel on he's great invention that were all benefiting from. Also great analogy on the internal combustion engines. We did have an engine that ran on diesel, mogas, kerosene and JP-8 fuel when I was in the US Army. We also could mix the fuel but it ran like crap when we did.I believe it was M35A1 on a deuce and a half truck. I want to say Hercules Diesel was the manufacturer. Thanks
JSL
+Joel Lagpacan I wasn't going to say the "don't mix the fuels" part in the video, but I don't want someone putting Diesel in their gas car to increase the mileage.
nice video thanks for sharing.
great informative vid thx
without watching i can take a guess as to why. energy density. now to see if im right? love the channel, thanks.
Good stuff thank u
Great video! How do gasoline injected engines compare to regular gasoline and diesel engines you have explained here
Modern emission regulations are killing the diesel engine worldwide... So unfortunate, I love everything about diesels
my honda civic 2.2 i-ctdi gets 57mpg on mormal driving being sensible sticking to speed limits and being smooth 😆👍 but if i drive like a maniac and tear it around the place like i stole it 😈 it gets 40+mpg 😊 unbelivable i love diesels 👌
RPM range is another cause that diesel engines have better MPG... very nice explanation.
this past July, I drove my Smart Car diesel from Canada to Nebraska
checked and double checked: 996 miles:
62.5 U.S. gallon per mile
the engine is 3 cylinders, 900cc
had lots of power. No problem keeping up with traffic or passing, but I did keep it about 60 mph in an attempt to get the best mpg possible
I'll never sell the car - love it.
+badgeless I didn't know they made a Smart Diesel, that is pretty impressive mileage.
can't buy them in North America anymore for some reason.
I don't know how they get adequate power out of it but I'm happy with it. The engine is a fascinating little 3 cylinders that sits sideways under the rear deck. the length of the engine is about 24 inches.
Not sure if you're in Canada, but if so you'll know about the Webasto coolant heaters. I've got one on the Smart. It can be -30 and the Smart not plugged in. I just flip the heater on and go back into the house. 15 - 20 min. later it fires up just like summer. If I leave the Webasto running while I'm driving it continues to heat the coolant as it circulates. 15 min. later, or so, I have to reduce the interior heater motor speed because it's too hot.
I love my Smart Car. Ugly but cheap. I'll never part with it.
badgeless Nice!
Adept Ape I thought all Smart cars were powered by gasoline, I did not know either.
At 62 gallons per mile, I would drive it to a Cadillac dealer and trade it in before I even started. Did you have a tanker truck following you?
Another thing i would like to add when it comes to the diesel vs gas debate as well is when it comes to tuning/modifying the engines. A diesel engine responds a lot better to mods than what a gas engine does, GM's 6.6 Duramax is an intake, exhaust and a hot & smokey tune away from 500 horsepower where as an LS1 is heads,cam,Intake and a 100 shot of nitrous away from the same power level. (Granted the LS1 is 50 ish cubic inches shy of a Duramax displacement wise)
shortfuse1993 because of turbo diesel vs n/a gas. A turbo ls1 would also easily make 500hp.
Not bad. Thank you.
My 15’ 5.7 4X4 TSS DC TUNDRA gets about 17.8 unloaded going down the highway here in Texas. During winter time I get 18. Dads 2007 Bulletproofed 6.0L he gets 22 MPG unloaded down the highway
My truck is a hybrid and I get 30 mpg. I have mexicans on treadmills with vr headsets of ICE coming after them.
At tickover speed the turbo provides no increase in air volume into the cylinders because it's not spinning fast enough , also when you stop accelerating and start cruising the turbo does nothing. So it's then back to suction to draw in the air on the induction stroke.
the biggest and main reason is because of the cylinder pressure at TDC. if gas did not predetonate it would get similar gas mileage to diesel. from the calculation of the PV curve of this adiabatic type compression, efficiency of the system increases with compression ratio or equivalent compression ratio (boosted).
what you said....
Devo well, if wishes were horses, beggars would ride... gasoline would predetonate and destroy the engine at those high comporession ratios..
Ya well... when you accidentally put diesel in your pressure washer when mixed with a little gas it’ll run about half choked and man did it have some torque!!
Thnks for the wonderful explanation i am gettin into diesal car and i need to know if i will save money in the long run owning a used 07 to 13 vw wagon since they just got sued and it is cheap right now. I am tired of filling up gas and i think its a money pit for my daily driver plus petro is a game that the Gov plays on us! What do u think?
The best way to compare an engine enficency is to compare engines with the same power (Gas and diesel)
I bought a new 2016 Canyon 2.8 duramax. I was scared to buy it on the first year. But needed a new truck. Do you know of any issues I should be worried about? Is this motor going to treat me good?
Reasons why diesels get good mpg is due to the viscosity of the diesel. The fuel is just like cooking oil that needs more heat to ignite than gas so refueling is a bit less likely to happen in diesel cars than gasoline cars
Correct observations there, although I don't think the comparison between a N/A gas engine and a turbo diesel is on point. Bettter compare N/A to N/A or turbocharged to turbocharged. Cool vid though!
back in the early 80's almost all car models had an option for a small 4 cylinder diesel with a 5 speed manual transmission Toyotas Ford escort chevetts and even a Nissan Maxima cause my uncle owned one but for some reason this died out . probably because the fuel got more expensive and early diesels had trouble in the cold starting? not Shure I was only about 6 years old then.
The Datsun Maxima was RWD and used an inline 6. In 1985, Nissan introduced a FWD Maxima, and gave it a V6 engine. Nissan didn't make a V6 diesel to match.
Another reason diesel sales declined in the USA was because people were less worried about fuel shortages and rising fuel prices. At that point, the added cost of a diesel was no longer justifiable. In addition, the Oldsmobile 350 really tainted the name of Rudolph Diesel. Only Mercedes-Benz had built a good reputation for diesels before the Olds 350 went on sale.
Excellent video. With the advantages of diesel vs gasoline, it's damn unforgivable that more diesel powered cars and light trucks aren't available here in the USA. I've never understood why that is. The EPA wants us to drive fuel efficient vehicles, cars that can drive up to 400 miles before refueling. Unfortunately, they're refusing to allow small displacement diesel engines to be offered.
+Jason Carpp It is unfortunate, unless you want an F350 you aren't getting a Diesel in the USA. I mean the EPA let a few slip through the cracks, but there should be a Diesel version of just about every model. Now if people would buy them here is another question.
I don't need an F350. They're nice trucks, but they're too much vehicle for what I need. I'd be happy with a Toyota Tacoma, or a 4Runner.
+Jason Carpp If Isuzu would put one of their exceptionally long lasting Diesel engines in a Toyota that could be a very good vehicle with great power and longevity.
I totally agree with you. For the Tundra, the Sequoia, and possibly the Land Cruiser, I would love to see a Baby Duramax diesel installed. :)
I'm all for clean air emissions, but this is bullshit. Who the hell is the EPA to decide what kind of engines are sold here in the U.S.A.? That's never made sense to me.
Can diesel engines actually run on used motor oil as fuel or vegetable oil?
Your best answer is to direct you to a library where you will find books that give you a picture type diagram of the OTTO combustion cycle versus Dr. Diesel's cycle. Basically, the OTTO cycle is combustion at constant pressure, whereas the Diesel cycle is combustion at constant pressure. But be careful here as Boyles law that you should have studied in high school physics gets right into the middle of everything.
My c15 is barely getting 5 mpg and it runs great..
Is this common?
You didn't talk about the different ignition sources. Diesels have to run unthrottled because they rely on the heat of compression to ignite the fuel as it is injected into the combustion chamber. If restrict the amt. of air lower compression lower heat no ignition. They are also much heavier. as the combustion event is more violent and really hammers the engine internals such as pistons rods crankshafts ,etc..
citroen c3 ehdi 2012 1.6ltr 93 hp : 46 Miles per gallon combined. 0-100 in 11.3 seconds. top speed 121 Miles per hour.
Awesome explanation. While talking about foot-pounds of torque you said: "this isn't to say that diesel engines are cheaper." Were you referring to the cost of ownership relative to the same for a gas engine? Sorry only point I was confused.
+Matthew Alan Thyer Initial purchase cost is usually much higher for a Diesel.
Yeah I'd agree with that. The good news is that over the lifetime of the engine operating cost tend to be less.
The real question is, is it more economical to buy the diesel model with it having a higher purchase price, maintenance expense, and fuel prices, vs the gas engine?
Generally yes in the long run. Tend to have a resale value higher than the gasoline counter part. Generally longer service intervals, better fuel economy. Longer engine life. My 2014 VW Jetta TDI. 6 speed manual averaged 48.5 mpg. With a best tank of 54.4 mpg.
Is this the reason why diesel engines take longer (in some cases much longer) to get to temperature than gasoline ? I have an 06 Mondeo 2.0 diesel which you can let idle in winter until the next day and it will not get to 90 unless you drive it. And yes, the car is ok technically - had it triple and double triple checked and both thermostats are replaced with OE ones.
You use less fuel to idle a diesel than you do a gas engine. In fact, at the end of the day, before I shut my truck off, I would let it idle in order to cool down my turbochargers and bring down the temperature of my coolant.
Your voice sounds like Cleveland from family guy.
what would be then the advantage of choosing a gasoline engine, besides price?
If something goes wrong, diesels are more expensive to repair than gasoline engines. The price difference got even worse as diesels were fitted with a DPF and later fitted with an SCR. EGR systems in gasoline engines are also far less expensive and labor intensive to repair, and some gasoline engines don't even need EGR.
hey adep ape i have a marine diesel engine 3406E i was wondering what are the cause of high oil pressure
+Dax Cassini High oil pressure eh? How high? Did it just go up for recently?
we yous when out for a run and the port engine pressure started to go up the gage was blinking red
normally its running around 80 psi
+Dax Cassini First thing is put a mechanical gauge to verify the pressure is up, then I would cut that filter open to see if there is any metal in there. Could be the pressure relief valve stuck closed or possible something worse like a plugged galley or something. Check that filter first.
So what's the difference between diesel mechanics and auto mechanics?
Sterling engine can run on gas or diesel
Fine, for the most part, but there is one thing you did not get quite right.
You should have compared a normally aspirated Diesel engine with a normally aspirated Otto-cycle engine. That would have removed one complication with the comparison. You stated that on a turbocharged Diesel engine, the pressure from the turbocharger helps to force the piston down during the intake stroke. Fine, but that doesn't actually help since the turbocharger gets its ability to do that by stealing power from the engine by increasing the exhaust back pressure.
The most important reason that a Diesel engine is more efficient, but not the only reason, is that it has no throttle valve and therefore the engine does not waste power sucking in air against the vacuum created by the throttle valve. A very important source of inefficiency with the Otto-cycle engine is the waste of power to suck air in against the vacuum created by the throttle valve. When running at full power, the efficiency difference between a Diesel engine and an Otto-cycle engine is far less because then the throttle on the Otto-cycle engine is fully open and creates no efficiency-robbing vacuum.
It is possible to eliminate the camshaft to get perfect valve timing under all conditions by using a computer controlled accuator for each valve. That can eliminate the throttle valve by one of two methods: 1) It can control the power by opening the intake valve only briefly when full power is not required. That way, the vacuum created when the intake valve is closed will help pull the piston up again during the early part of the compression stroke thereby recovering the power lost by creating the vacuum. Or, 2) It can control the power by delaying closing the intake valve until way past bottom dead center when full power is not required thereby not creating a vacuum but letting air escape from the cylinder until the valve closes. Either of the two methods can control the power with no throttle valve thereby eliminating the inefficiency caused by the throttle valve.
The reason this is not been implemented is that it is very costly, but it has been successfully tested. In addition to greatly improving the efficiency of the Otto-cycle engine, it can also increase power and flexibility by having ideal valve timing for all engine speeds.
A unit of diesel fuel (gallon, gram, or bucket) contains more energy than the same amount of gasoline. Is it so surprising that you would require less higher energy fuel to do the same work as the less energetic fuel?
I agree with everything but your explanation of the turbo and the pressurized air thing. The turbo is being turned by the exhaust, so the piston on the power stroke that is pushing the exhaust stroke on the other is doing the work of pressurizing the air. You didnt really explain it wrong, just not fully. I think that it would be better to describe the turbo as a method of capturing energy that would otherwise be lost out the exhaust pipe.
i just came in to your video's, love them! but can you (for fun) give a mechanical diesel engine a bit more power and rolling coal (i know its stupid but i just want to know lol)
+offroad idiot Are you asking if a mechanical engine can be made to roll coal or are you asking me to do a video on how to crank them up?
not really a video if it is easy to say it in the comments, but im wondering for a long time about this
offroad idiot Rolling coal is just running rich. Get bigger injectors or increase fuel flow without changing air flow and you'll "roll coal"
Isaac record in theory i know the deal, but in practise i dont
So a turbo in a gasoline vehicle it gets extremely hot and needs its own active cooling. So if the thermal efficiency is better in the diesel, does the turbo not get as hot? If so do these turbos last long?
Samuel Johnson Most modern diesel engine turbos are now coolant and oil cooled. My 6.0 PS will climb to 1400 degrees on the exhaust side of the turbo under heavy load at WOT
I never knew there were "calories" for fuel volume. I've learned the fuel to air ratios are a lot different to combust. Correct me if I'm wrong; diesel combusts at a 300:1 ratio and gas is 60:1 fuel to air... ?
+Nathan Springer Gas should be around 14:1 ratio, Diesel uses usually a much higher ratio of air compared to gas since they nearly always run lean, but 300 to 1 would be a very lean condition.
+Adept Ape Thx for clarification.
I drive a diesel car...love it
I have question for you that is bugging mi for long time. Why naturally aspirated diesel engine makes much less power for same displacement than naturally aspirated gasoline engine. for example 1.9SDI (VW engine) 65HP vs 1.6FSI 115HP (Audi engine)?
It is even stranger because diesel have more energy per gallon than gasoline.
+Marjan Markovic Its really due to the torque range, Diesels usually make much more torque, but at a lower rpm. Since horsepower is just an equation of torque times rpm divided by 5252 and Gasoline engines make less torque, but at a much higher rpm, they make more horsepower.
There is a major aspect between Diesel and spark ignition engines that is very deserving of detailed discussion and that is spark ignition engine's combustion propagates by flame front from the spark source. A compression ignition engine detonates its individual fuel particles everywhere. There is no traveling ignition flame. Detonation engines as a scientific topic implies the shockwave travels faster than the speed of sound which is suppose to be more efficient than simple gas expansion in rocket engines. This topic, with the available information commonly available, is frankly a bit bazar. The detonation process in a Diesel engine may provide much higher efficiencies than the spark ignition burn process.
In heavy duty over-the-road Diesels the need for a powerful reliable dynamic brake provided by the Diesel Jake brake makes the Diesel not realistically replaceable by spark ignition engines. There are many fuel markets today where a heavy duty high efficiency gasoline engine might be cheaper to fuel than a Diesel. There are no heavy duty gasoline large displacement low reving engines with replaceable cylinder liners and such. Nothing that is comfortably on the market. The the high reving Ford V10 OHC gasoline medium duty gasoline truck engine is the closest example I know of. That appears to be a 300,000 mile engine.
How about comparing new diesel engines vs old non egr diesel engines. New diesel engines make more power on average, but also get less mpg. Example VW TDI engines.
On the truck engine put in your car. Of course it won't get good mileage. Higher horsepower engine=lower mpg. The newest thing to come out is LNG or CNG engines. These engines burn really inexpensive fuel (Here gas is about $3 to a gallon, and LNG/CNG are about $1.3 to a gallon). However, LNG and CNG have much fewer calories per gallon, about 1/2 as many as gasoline. Therefore, a tankful will only go about half as it would on gasoline. A lot of people don't like diesel, because it's "more expensive." But, they forget about "more efficient."
doesn't gas engines run at the high 20's in thermal efficiency while diesels run in the mid 30's and the huge diesels that are in ships run closer to 50%? Also isn't the maximum theoretical thermal efficiency of an internal combustion engine 64% thermal efficiency?
If i remember the old cat d8 14a will run gas/diesel. starts and warms up on gas then you switch to diesel.
+Trixler293 That must be quite the engine, how old was it?
Should be in the late 40s through 50s. Also a IH Farmall D450 starts on gas and runs on diesel. 1953 international TD20 bulldozer too, I was trying to find a particular video it had spark plugs and distributor. you move two levers one for diesel fuel and the other to raise the compression. Lots of 50s earth movers started on gas, i guess because glow plugs werent around yet.
We called them pony motors, and you are correct about the glow plugs.
okay I believe in two stroke extreme boost diesel. think about that one. how about a.wankle engine with the new port configuration which has put it back into R&D and it should be a major interest IMO.
That would be interesting to see how the mechanical inefficiencies are overcome. There are many smart engineers out there.
Why can't they control a throttle on patrols with the injectors like Diesels?
Compare the 2.7 liter F-150 EcoBoost to the 3.0 liter Ram 1500 EcoDiesel and you'll see that there's no benefit to the diesel. The diesel costs more to fuel, has greater CO2 emissions and the EcoBoost has 85 (yes, 85!) more hp. Same thing happens if you compare the 2014 base model Accord to the Chevy Cruze diesel, the diesel costs more to fuel, produces more CO2 and has less power. Same thing went for the Golf TDI and the Honda Civic, except they were equal in power output. I could go on and on, there's just no benefit to diesels.
+idontcare80 I mention in the video that Diesels cost more, which is true. The mileage increase usually doesn't make up the cost difference between the increased cost of the engine, maintenance, and usually higher fuel cost. I'm going to make a video about whether Diesels save you money compared to Gas in the future.
It's not just about money, it's about emissions, and performance. In Europe, some politicians are apologizing for pushing diesels because the widespread adoption of diesels has created serious smog issues. Some cities are even considering banning diesels from their roads because they're so polluting.
www.bbc.com/news/science-environment-38170794
Question! Are diesel engines 2 stroke? where gas are 4 stroke.
+Albion Laster Most Diesels are 4 stroke, but Detroit Diesel made several 2 stroke Diesels, but I believe they have been out of production for a while.
I think that BTU's, not Calories are the correct measurement for combustion efficiency comparison ??
+vaccumme You can use either, they are both thermal units of measure. One converts to the other. I used Calories because a lot of people are familiar with them in food energy counting.
Well Said. Thank you.
3:09 except for a deuce and a half
One small nit, sucking vs turbo efficiency, the energy to drive the turbo isn't free but comes from exhaust gas. One way or the other the engine is working to pump air through the cylinders. Gas or diesel, turbo's improve torque. But with turbo's the more the boost the more the power, so it is kind of a mistake to even bring them up. What I would like to know is why are manufacturers like Porsche and Ferrari so keen on high-revving motors over high-torque low rpm engines? Because they sound like F1? So why are F1 engines all high-rpm? (I know, because…. rules…)
Why don't they make over built gas engine that run at crazy compression so they stay strong like the diesels but run more efficient?
The same model equipped with a 3-liter gasoline engine will always be thirstier than a 2-liter diesel one. Diesel engines will most of the time be more fuel efficient when compared to same capacity gasoline engines. However, the economy of a 3-liter diesel engine will often be similar to that of a 2-liter gasoline engine. It's hard to understand why didn't you compare same capacity engines. Maybe I'm missing something. Edit: Sorry! Should have watched the whole video before playing the smart-ass number.
Absolutely correct!
The differences end up washing out in the price difference at purchase time and the price of fuel. If diesel fuel and gasoline were priced the same, then the savings would make purchasing a diesel vehicle justifiable.
+Steve Ross I never say in the video that Diesel is cheaper or cheaper to operate. It is nearly always more expensive, just more fuel efficient.
Steve Ross at a lot of gas stations in my area, diesel is the same price or slightly cheaper than regular unleaded. If I had the money, I would've bought a diesel instead of my Galant, but there weren't any in my price range that didn't need lots of work.
In Europe diesel it's cheaper than gasoline and many companies offer diesel version at same price of the gasoline version.
I nvr use milk in my diesel...
If gasoline combusts at a lower temperature,why not run a higher compression ratio and inject the fuel just before top dead center like in a diesel? Wouldn't this give you more torque?
In theory, it sounds good, but, in actual practice...what would happen if you put gasoline in a diesel engine? I know someone who had to deal with that very issue...some dummy had done that very thing. It didn't work out too well!!!
NiceMuslimLady what happens exactly? I could see it eating away at certain seals and whatnot,but if you engineered it in a way with the proper materials I don't see why it wouldn't work. I'm not saying I'm not wrong,but I can't seem to find an answer yet.
Zack Fraser To my knowledge, the fuel would probably combust, but not efficiently as it has little time to mix with the air it needs.
Ford did this with their Eco Mustang. And yes it works.
I'm looking to buy an older school or shuttle bus could I get your opinion on the best engines please? THANKS
+mountainman For a Cat I would go with a 3126, they are good small Diesels. A gas engine is a lot cheaper though, what are you using the bus for?
Cross country rv conversion. I'm 42 and experiencing unexpected health issues and want to travel the west and maybe the north east but think it's more difficult cheaply anyway.
Adept Ape I'll try to pm I could really use some good advice. Thanks
mountainman Please email me at AdeptApe@yahoo.com the PM feature on CZcams is horrible.
mountainman If you are willing to go older and mechanically injected, the best engines are the International DT series. Unlike the smaller Cats, these engines are wet sleeve like the big diesels so doing a rebuild is easier, parts are cheap and plentiful and it has really no serious weaknesses. A DT360 or 466 will last you a long time, and if it has an inline injection pump can make more than enough power inexpensively. The HEUI system on the DT466E is the same basic design as the system used on CAT engines ( CAT and Navistar collaborated together ) but nothing is cheap about fixing them. Most common problem is the cam sensor going out.
TDI 4 Life
Why don't petrol engines use some type of governor to control the throttle
Some tractor and industrial gasoline engines do have governors.
explain this, a 7.3 idi gets 30mpg hauling a trailer with no turbo. but a 7.3 powerstroke gets 11mpg hauling the same trailer. the idi non turbo gets so almost 3x better fuel economy than a 7.3 powerstroke does. so is the your turbo suggestion false? they both have 3.73 rear end, both have a 5 speed. both f250. same exact truck. the difference is the non turbo gets 3x better fuel economy.
I disagree with a few things:1. A long stroke does NOT make greater torque. The low RPM of a long stroke engine is determined by the safe mean piston speed.2. You cannot compare turbocharged diesels with naturally aspirated petrol engines.3. The diesel engine's efficiency at part-load is due to its running lean, while a petrol engine has to maintain a near-stoichiometric air:fuel ratio. The petrol engine accomplishes this by throttling the air in the intake, which causes severe pumping losses.4. An efficiency of 45% is a bit high, even for a turbodiesel at torque peak. I don't even think a gas turbine is that efficient. A turbodiesel has a peak efficiency of closer to 35%, and a petrol engine closer to 27%. Of course, it is important to state the measure of efficiency. I base my number on an isentropic efficiency, which works relative to absolute temperature and absolutely lossless and reversible processes. Maybe you use a different measure of efficiency.Great show, keep up the good work.
This makes diesel better? What are the disadvantages of diesels?
dallatorretdu higher emission in some cases
Diesels usually cost more money to build, and since 2008, the price difference became far worse due to the use of the DPF.
Too bad diesel gets a bad rep for being dirty. Alot of countries in europe are banning diesel engines because of pollution. Eventually they want to get rid of gas too. That will force the governments to give us alternative fuels we've already had for decades that are less polluting
leadnsteel on the contrary, Europe has a higher proportion of diesel vehicles than the US. Diesel is actually a bit cleaner emissions wise especially when a DEF tank is used.
Cars burning calories im dead
And the age old question why gas engines rumble and diesel engines pop.
You skipped the emissions part...
Deisel engines run slower rpms therefore burn less fuel diesel engine 3 thousand rpm max gas engine 6 thousand rpm max
you italian or what?
Multifuels run on this concept... but they are super inefficient.
diesel for its injection system
I like the videos but try to shorten them up
Damn I’d be fat af if I drank diesel
what about turbo gas engine more air more fuel bigger bang more hp. just asking
Yeah, but it's not efficient as you need to add more fuel to keep the air/fuel mix at a level that it will ignite....but more hp than the same size diesel engine.
That is great, so long as the gasoline engine is run off boost most of the time.
$
6 minutes of waffle before you actually hit on the main reason, a petrol (gas) engine runs a throttle which is virtually shut when the car is cruising along. This means that the volumetric efficiency (VE) is low, the pressure in the combustion chamber before the plug fires in low which as a direct result on the peak cylinder pressure, in other words it is also lower than ideal. A diesel engine is not generally throttled (but some now have turbulence plates), the engine is only controlled by the amount of fuel being injected, it always operates at least 100% VE and generally more due to the turbo. The peak cylinder pressure is much higher because of this and it is this pressure above the pistons that produces torque.
The 'less friction' reason and most of the other stuff is so minor that it is not even worth mentioning. What we need is a petrol engine that runs at 100% VE (or more) that is controlled by fuel only but this is not really possible because if you lean the mixture off too much in a petrol engine it simply won't ignite. (Lean mixtures have other issues too). If we could fill the cylinder with fresh air then somehow inject an air/fuel gaseous mixture in at around 14:1 ratio just around the spark plug and use this to control the engine that would work. We would then have a petrol engine that would have the MGP of a diesel. Unfortunately it is easy said than done! Whilst we are at it fully variable valve timing along with a variable compression ratio would be nice!
My fiance and 1 both own dodge rams same year's 2005. Mine is a cummins his is gas. We filled up in kansas at the exact same times with same size gas/feul tanks and both have no after market mods. We both traveled from kansas to AZ and has milage for both are almost the same. Everytime we filled up the gas /fuel needles are in the exact same position in both trucks. There is absolutely zero difference in feul milage in gas and diesel. Unless you have actully done this comparison on a road trip with 2 identical situations just one diesle and one gas then your spewing crap. I did this half way across the country with identical driving and load situations.
Diesels rock, a german invention...
Obey acts 2:38
I used diesel to light a bonfire and it burned way longer than gas