Each engine has a Brake Specific Fuel Consumption map, in which the engine is most efficient at certain RPM's at certain engine loads. You should aim to attune your driving to that, too slow and the friction lowers fuel economy, too fast and the engine friction increases too much as well.
Yes ideally you want to keep the rpms at the point where the bsfc is minimal for a given amount of power used. Most engines are most efficient around 80% load at or just below the rpm of maximum torque. This is part of the reason why hybrid cars are so efficient, as they keep the gas engine closer to its optimum bsfc, allowing it to run more efficiently.
@@Gnerko123 both are for the most part true. Both try to run at an optimum RPM. I’ve driven a Mitsubishi Outlander PHEV and that thing only turns on its engine when the battery is low or when it needs extra oomph. It will start, run at an optimum RPM (which is mostly a fixed RPM depending on load) and then turn off again. I’ve also done a lot of different sizes of festivals in the countryside that needed power sources ranging from the smallest (petrol) generators up to the container diesel generators. Their RPM’s are constant when the load is constant. When the load changes the RPM’s will change as well. It makes sense also because with no load the only task for the generator is keeping itself running. When the load goes up it needs to work more so the RPM’s usually go up until you’re really working the generator, then you’ll hear the RPM’s drop and the drone of the engine get louder (not unlike putting a car from P to D, but then with a tad too low of an idle).
Here's my anecdote. I drove a 1998 Saturn Sl1 , I spent a couple months running an experiment with limiting my RPM, and therefore my acceleration, to speed. I limited my RPM to 1600, 2000, 2500, and 3000. The 1600 rpm run was the one I consumed the most fuel. The engine speed to fuel economy ratio seems to have a bathtub curve, just like speed does for fuel efficiency.
First of all, you have to differntiate between diesel and gasoline engines, because gasoline engines always drive "same mixture" (kind of, +/-10% depending on load), but have a throttle valve for power regulation. I tuned my car by myself with a completely free programmable open-source ECM, and the correct tables that came out shocked me. Even if i am completely decelerating, the engine gets 60-70% volume/fuel. At a power of 0hp. That means, that all of the power these 60-70% volume/fuel could generate will be completely consumed by sucking air from the closed throttle valve. Long story short: It is efficient to accelerate fast, with WOT, in low gears, but then roll in very high gears. The bigger problem is, that if youre in this mode, like in this video, you are driving like a heck. Unneccesary acceleration, often braking, too high speeds, and so on......
Absolutley agree. Although it seems interesting, that your ecu is still injecting fuel during deceleration. With my car it then stops injection because the engine is running on its own (spun up through the wheels) But yeah driving like an idiot is the real problem here. I wasn't setting out to make any scientifically accurate video, just wanted to have some fun. But if you stick to the necessary accelerations and drive at speed limit accelerating quickly will often be more efficient
@@MichelsGarage This is another feature i have deactivated during setting the ve tables correctly. This feature is now re-activated, while decelarting, i do not have any fuel injected now.
If you have a manual transmission or an automated manual and use lots of throttle input but short shift the hell out of it, you will have the most effecient acceleration. The reason is that fuels burn more completely at higher pressure, while using less combustion cycles to get up to speed. After that, shift into the highest gear possible to maintain speed. But be warned, overdoing it can cause low speed pre ignition. (Knocking or pinging)
I think it’s not very deep. Accelerating faster means your car will suffer from wind resistance/drag earlier, inducing losses. It also means that this kind of driving is not anticipatory, meaning you’ll have to brake more often, wasting energy. Your principle is correct (as engine efficiency) but it doesn’t work in the driving world
The best fuel economy is to stay withoin 1 to 2k rpm period dont push the gaspedal further than whats needed, you are wasting fuel then. also remember to kiss the red line once a week to clean the engine :D another thing city driving is worst for economy you should aswell use the start/stop system in the cities if available
Fast acceleration takes more fuel, but you must make more tests with low traffic and no red and green lights. You must make 5 tests each at least and in same traffic conditions. If you like to drive gas pedal to the metal, then deal with higher fuel consumption. Fast acceleration needs a lot's of energy, this is the reason why 5 second car must be very powerful.
Yes you're absolutley right. This was just fooling about not really any scientifically accurate testing. But there's probably a curve to which extend accelerating faster can save fuel. Because I'd argue, that accelerating to 100kph in 2 minutes will probably use more fuel than doing it in in 20s
I drive an electric car so it's really simple: the faster I drive, the worse the efficiency. 10 miles charge will be gone in 2 miles. Don't drive electric, folks.
Mit meinem ersten Auto (Honda Accord Type R) habe ich dauerhaft Teil 2 des Experiments durchgeführt. Spaß war keine Frage, aber es war definitiv nicht sparsam (20l/100km) :D
in my head thats pretty obv pedal to the metal just means faster engine rotation so i would ATLEAST think it uses the same amount of fuel but who am i nice video man !
if i accelerate slowly i get about 5.5L/100km in daily traffic, if i accelerate fast everywhere (and just drive fast in general) i get about 13L/100km, but i can tell you which is way more fun, so 13L/100km it is
@@justinanderson181 That's just what BMW and VW (BMW drivers at heart but with less money) are like. It's not a cultural thing it's based on German cars - Audi and Merc drivers are assholes too.
Accelerating quicker means less fuel is used to reach the speed, but you will spend more time traveling quicker (air resistance=velocity^2 ) so overall you will spend more time at a higher speed so fuel consumption goes up
@@MichelsGarage because you reach the speed quicker. The time/distance you spend accelerating is time/distance spent driving slower then once you reach the speed
Going Faster does not mean Higher fuel consumption, there are plenty situation where my car does Higher fuel consumption at lower speeds because you may have to use lower gears , my car averages 4.0 l/100km at 140km/h while the overall average consumption is 5.8l/100km so at higher speeds it's more economical
@@manuelventura3799 that's anecdotal evidence, physics formulas prove that at high speeds the biggest factor in efficiency is drag, and while gearing (and engines efficiency at certain rpm's) plays a role in that, the faster you go the less of a factor it becomes.
Diesel engines are technically most efficient at 100% load. Well, there's my bit of useless information for everyone today 😂 Edit. Just to correct my post, as it wasn't 100% correct... Diesel engines are often most efficient when operating between 75% to 100% of their maximum load capacity. This range allows them to work closer to their optimal operating conditions, improving fuel efficiency. However, actual efficiency can vary based on engine design, load type, and other factors. Please note this based on the engine not the application.
@kaliikleja Diesel engines are designed to run at 100% load. It will be the most fuel efficient based on power output at full load with a fixed RPM. Don't believe me, look at any diesel generator fuel consumption chart. If run you the engine at 50% load (constant rpms) for an hour and measure the fuel consumption. Then do the same test at 100%. You will find, it would have used just less than double the fuel it took at 50%. This test can not be easily replicated in a car, due to inconsistencies in the test and obvious driving factors. Put it on the test bed you will find, I'm correct. I prove this at least once a week on load tests i carry out for my occupation. Hope everyone had a lovely break over Christmas and wish you all the best in 2024. Thanks for the comment, i appreciate that not all engines are the same, but feel free to prove me wrong with your own test 😉
@@balders6095 Engines are designed to run at 100% load for failure rates, if lower failure rate is acceptable, then more power can be produced. Hence why a Mercedes engine cna be 2x more powerful in a hypercar, as failure rates in a £2 million car, won't matter as much. Diesel vehicle engines and diesel generators are very different, hence you don't see a 2.0 PSA HDi or 1.9 TDI VAG engine used as a generator (commonly) and vice versa. If you look up Brake Specific Fuel Consumption maps of diesel engines, there is no automotive engine that is most efficient at 100%. The 100% load on a generator will be held there because it was the most efficient point but that engine will be capable of producing more power.
This myth might be true for really old cars but nowadays the engine control unit is smart enough to optimise fuel consumption for any rpm and acceleration.
@@Henrix1998 long accelerating is not a problem because it takes a lot less fuel and so it's duration may be longer. Of course there is some limits how slow, but normal a little bit slower type acceleration is very good.
Each engine has a Brake Specific Fuel Consumption map, in which the engine is most efficient at certain RPM's at certain engine loads. You should aim to attune your driving to that, too slow and the friction lowers fuel economy, too fast and the engine friction increases too much as well.
Thank you for the info!!
Yes ideally you want to keep the rpms at the point where the bsfc is minimal for a given amount of power used. Most engines are most efficient around 80% load at or just below the rpm of maximum torque.
This is part of the reason why hybrid cars are so efficient, as they keep the gas engine closer to its optimum bsfc, allowing it to run more efficiently.
@@Gnerko123engines in hybrids, especially with CVT or without a direct connection closely resemble a power generator.
@@RustOnWheels In my understanding, power generators are often designed to run at a single rpm. Hybrid car engines run at a wider range of rpms
@@Gnerko123 both are for the most part true. Both try to run at an optimum RPM.
I’ve driven a Mitsubishi Outlander PHEV and that thing only turns on its engine when the battery is low or when it needs extra oomph. It will start, run at an optimum RPM (which is mostly a fixed RPM depending on load) and then turn off again.
I’ve also done a lot of different sizes of festivals in the countryside that needed power sources ranging from the smallest (petrol) generators up to the container diesel generators. Their RPM’s are constant when the load is constant. When the load changes the RPM’s will change as well. It makes sense also because with no load the only task for the generator is keeping itself running. When the load goes up it needs to work more so the RPM’s usually go up until you’re really working the generator, then you’ll hear the RPM’s drop and the drone of the engine get louder (not unlike putting a car from P to D, but then with a tad too low of an idle).
Here's my anecdote. I drove a 1998 Saturn Sl1 , I spent a couple months running an experiment with limiting my RPM, and therefore my acceleration, to speed. I limited my RPM to 1600, 2000, 2500, and 3000. The 1600 rpm run was the one I consumed the most fuel. The engine speed to fuel economy ratio seems to have a bathtub curve, just like speed does for fuel efficiency.
Absolutley. It's not a yes or no answer, that's what I tried to convey in this video :)
And of course thank you for your insights
Just found your channel. Great content, keep up the good work
Thanks! Glad you like it :)
I really woundt worry about fuel consumption on a 1.2-1.5l engine.
First of all, you have to differntiate between diesel and gasoline engines, because gasoline engines always drive "same mixture" (kind of, +/-10% depending on load), but have a throttle valve for power regulation.
I tuned my car by myself with a completely free programmable open-source ECM, and the correct tables that came out shocked me. Even if i am completely decelerating, the engine gets 60-70% volume/fuel. At a power of 0hp. That means, that all of the power these 60-70% volume/fuel could generate will be completely consumed by sucking air from the closed throttle valve.
Long story short: It is efficient to accelerate fast, with WOT, in low gears, but then roll in very high gears.
The bigger problem is, that if youre in this mode, like in this video, you are driving like a heck. Unneccesary acceleration, often braking, too high speeds, and so on......
Absolutley agree. Although it seems interesting, that your ecu is still injecting fuel during deceleration. With my car it then stops injection because the engine is running on its own (spun up through the wheels)
But yeah driving like an idiot is the real problem here. I wasn't setting out to make any scientifically accurate video, just wanted to have some fun. But if you stick to the necessary accelerations and drive at speed limit accelerating quickly will often be more efficient
@@MichelsGarage This is another feature i have deactivated during setting the ve tables correctly. This feature is now re-activated, while decelarting, i do not have any fuel injected now.
@@stonix1992 that seems logical. Thanks for the explanation!
If you have a manual transmission or an automated manual and use lots of throttle input but short shift the hell out of it, you will have the most effecient acceleration. The reason is that fuels burn more completely at higher pressure, while using less combustion cycles to get up to speed.
After that, shift into the highest gear possible to maintain speed.
But be warned, overdoing it can cause low speed pre ignition. (Knocking or pinging)
overdoing what? highest gear possible? or semi-WOT short shifting?
@@vertigoEdits overdoing it meaning lugging your engine. Every engine is different so the amount of throttle you can use at low rpm varies.
This guy is so underatted he needs more subs and views for his content fr fr :3
Thanks a lot!! I really appreciate the support; It really brightens up my day :) Hope you have a good start into 2024
@@MichelsGarage Wishing the same ❤️
I think it’s not very deep. Accelerating faster means your car will suffer from wind resistance/drag earlier, inducing losses. It also means that this kind of driving is not anticipatory, meaning you’ll have to brake more often, wasting energy. Your principle is correct (as engine efficiency) but it doesn’t work in the driving world
what a cool concept to test! new sub! keep it up my guy !
Thanks a lot my man!! Gonna definetly keep it up ;)
The best fuel economy is to stay withoin 1 to 2k rpm period dont push the gaspedal further than whats needed, you are wasting fuel then. also remember to kiss the red line once a week to clean the engine :D another thing city driving is worst for economy you should aswell use the start/stop system in the cities if available
Kissing the redline is always a good idea (:
(at least fun wise)
@@MichelsGarage you dont overdo it, if you do then it has a negative effect :P
Fast acceleration takes more fuel, but you must make more tests with low traffic and no red and green lights.
You must make 5 tests each at least and in same traffic conditions.
If you like to drive gas pedal to the metal, then deal with higher fuel consumption.
Fast acceleration needs a lot's of energy, this is the reason why 5 second car must be very powerful.
Yes you're absolutley right. This was just fooling about not really any scientifically accurate testing.
But there's probably a curve to which extend accelerating faster can save fuel. Because I'd argue, that accelerating to 100kph in 2 minutes will probably use more fuel than doing it in in 20s
I have the same car. Honda jazz. Nice video
Nice! A really awesome car :)
I drive an electric car so it's really simple: the faster I drive, the worse the efficiency. 10 miles charge will be gone in 2 miles. Don't drive electric, folks.
It's really incredible how fast your range can go down. But when using regen braking it's pretty impressive to see it go back up
Mit meinem ersten Auto (Honda Accord Type R) habe ich dauerhaft Teil 2 des Experiments durchgeführt. Spaß war keine Frage, aber es war definitiv nicht sparsam (20l/100km) :D
Da seh ich kein problem. Nh ganz simple rechnug: mehr spaß = besser
nice video man keep the nice content (refering other videos too)
Thanks a lot my man. Will do!!
lol the chris fix cameo in the beginning
The first one to catch it (or atleast comment on it)
Ha totally! I just scanned through the comments to see if someone got it xD nice one
Next video see if you can save fuel by not using the break ;D
Nice video mate, quite funny :P
What a great idea (:
Will definetly give it a try
Thanks a lot my man, glad to hear that!
3:18 that is some amazing chewie impression
Thanks. Been practicing that for yearssss, finally someone noticed😂
Your route looks like a weird toe, but thanks for this practical approach
Oh shit you're right! Didn't even notice it. Quite the funny looking toe 😂
in my head thats pretty obv pedal to the metal just means faster engine rotation so i would ATLEAST think it uses the same amount of fuel but who am i nice video man !
Thats also my thought! Thanks for your comment my man :)
if i accelerate slowly i get about 5.5L/100km in daily traffic, if i accelerate fast everywhere (and just drive fast in general) i get about 13L/100km, but i can tell you which is way more fun, so 13L/100km it is
The math checks out. More fun will always win
@@MichelsGarage Your math is sadly wrong, make more tests in same conditions no traffic.
Gib iiihhm!!!
Hellll yeahhhh!!
And I thought drivers in the USA were assholes
Are you talking about me? (:
@@MichelsGarage no the bmw driver and VW driver when you were turning
@@justinanderson181 yeah that's pretty average over here. A lot of impatient people. But most are really nice and look out for each other :)
@@justinanderson181 That's just what BMW and VW (BMW drivers at heart but with less money) are like. It's not a cultural thing it's based on German cars - Audi and Merc drivers are assholes too.
Accelerating quicker means less fuel is used to reach the speed, but you will spend more time traveling quicker (air resistance=velocity^2 ) so overall you will spend more time at a higher speed so fuel consumption goes up
I don't quite get your point. Why do you spend more time traveling quicker?
@@MichelsGarage because you reach the speed quicker. The time/distance you spend accelerating is time/distance spent driving slower then once you reach the speed
@sanderrehepapp5219 ah okay now I get you, thanks. Haven't thought about it that way, great thought!
Going Faster does not mean Higher fuel consumption, there are plenty situation where my car does Higher fuel consumption at lower speeds because you may have to use lower gears , my car averages 4.0 l/100km at 140km/h while the overall average consumption is 5.8l/100km so at higher speeds it's more economical
@@manuelventura3799 that's anecdotal evidence, physics formulas prove that at high speeds the biggest factor in efficiency is drag, and while gearing (and engines efficiency at certain rpm's) plays a role in that, the faster you go the less of a factor it becomes.
Diesel engines are technically most efficient at 100% load. Well, there's my bit of useless information for everyone today 😂
Edit. Just to correct my post, as it wasn't 100% correct... Diesel engines are often most efficient when operating between 75% to 100% of their maximum load capacity. This range allows them to work closer to their optimal operating conditions, improving fuel efficiency. However, actual efficiency can vary based on engine design, load type, and other factors.
Please note this based on the engine not the application.
Learning something new everyday. Thanks for your service ;)
No. Just simply NO!.
@balders6095 you talking total nonsense, diesel cars are not most efficient at 100%. no engine are efficient at this load.
@kaliikleja Diesel engines are designed to run at 100% load. It will be the most fuel efficient based on power output at full load with a fixed RPM. Don't believe me, look at any diesel generator fuel consumption chart. If run you the engine at 50% load (constant rpms) for an hour and measure the fuel consumption. Then do the same test at 100%. You will find, it would have used just less than double the fuel it took at 50%. This test can not be easily replicated in a car, due to inconsistencies in the test and obvious driving factors. Put it on the test bed you will find, I'm correct.
I prove this at least once a week on load tests i carry out for my occupation.
Hope everyone had a lovely break over Christmas and wish you all the best in 2024.
Thanks for the comment, i appreciate that not all engines are the same, but feel free to prove me wrong with your own test 😉
@@balders6095 Engines are designed to run at 100% load for failure rates, if lower failure rate is acceptable, then more power can be produced. Hence why a Mercedes engine cna be 2x more powerful in a hypercar, as failure rates in a £2 million car, won't matter as much. Diesel vehicle engines and diesel generators are very different, hence you don't see a 2.0 PSA HDi or 1.9 TDI VAG engine used as a generator (commonly) and vice versa. If you look up Brake Specific Fuel Consumption maps of diesel engines, there is no automotive engine that is most efficient at 100%. The 100% load on a generator will be held there because it was the most efficient point but that engine will be capable of producing more power.
This myth might be true for really old cars but nowadays the engine control unit is smart enough to optimise fuel consumption for any rpm and acceleration.
Atleast to a certain degree. It won't make pedal to the medal as efficient as "regular" driving
Faster acceleration takes more energy, this is physics law.
@@kaliikleja but then you don't need to accelerate as long
@@Henrix1998 long accelerating is not a problem because it takes a lot less fuel and so it's duration may be longer. Of course there is some limits how slow, but normal a little bit slower type acceleration is very good.