Here are two additional videos which supplement this nicely, hope everyone's having a great day! When To Shift For The Best Acceleration - kzread.info/dash/bejne/rI5208Rpiq25p7g.html LSPI: Don't Lug Your Engine - kzread.info/dash/bejne/paN-x8NwqKjaXZs.html

@fartingfury

5 жыл бұрын

Does this also apply to diesels, since there are presumably no pumping losses across the throttle plate to worry about, and where one needs to get the turbo spinning to get efficiency?

@acmaeve8269

5 жыл бұрын

Engineering Explained - Thanks for the next link. I am a 31 year old Mom that just got her license last year - had a huge fear of driving - and now I've been doing research because when I started driving I had a Jetta and I taught myself to drive in her. My next car, a Monti Carlo (did I spell that right lol) wasn't a manual and I hated it. She has problems with the transmission wasn't changing gears fast enough imo, and then she overheated and it went down hill from there. She's currently in the shop. My Jetta long gone by this point. So my Wife surprised me with a manual 95 Jeep YJ, she needs work done to her. Cosmentic and a few things under her Hood but for the most part she's perfect imo. Point of this comment is I've been watching a lot of your videos so I can tinker myself on the Jeep. And even though I taught myself to drive the Jetta, I don't know all the right ways, seeing as I know just because I can get it moving doesn't mean I'm doing everything right in the long run. Lol. So thanks for these types of videos! I need to get better at changing gears at the right time. With this video I now believe I have been changing gears just a bit too late in the Jeep. She's older than the Jetta was and I have to get used to how she ticks. Thanks for the help! :-)

@johngialampoukas311

5 жыл бұрын

The thing is, the bsfc maps are created at "steady state" conditions, which is close to what you show in the constant speed test. But acceleration is a "transient" condition, so how can you know where you are on the map?

@aussiebloke609

5 жыл бұрын

Some years ago, I recall BMW saying that for the best volumetric efficiency, they recommended flooring the throttle in every gear - and shifting at 1500rpm. This is probably a little extreme, but the principle is the same. I've used this technique on long road trips in an '01 Focus ZX3 (so I generally shifted at 2000 rpm to avoid lugging - it was not exactly a torque monster.) I achieved an average of 35 mpg, at an average speed (including stopping for fuel) of 65mph. All by using the maximum throttle opening I could use for the speed I wanted to do, and sticking to the highest gear I could get away with.

@pgtmr2713

5 жыл бұрын

My manual says something about NOT shifting to early. After 2 weeks trying to get better economy I ruined my cap, and rotor.

The best time to shift gears is when your right foot is touching the firewall and the rpm needle is sword fighting in the hotzone

@Welcometofacsistube

5 жыл бұрын

Stewart Mckinna well I was going to say something witty but you beat me to it

@toyotakp-36channel72

5 жыл бұрын

Stewart Mckinna Hahahahaha,the best comment that I saw in this week

@EngineeringExplained

5 жыл бұрын

And depending on what you consider best, sometimes true! kzread.info/dash/bejne/rI5208Rpiq25p7g.html

@TheTurpin1234

5 жыл бұрын

Fuel economy is lame. Gas is cheap. If you want to spend less on gas, get cheap beater cars.

@xkitejunkie

5 жыл бұрын

@@TheTurpin1234 depends where you live. In the UK regular unleaded is around $6.30 per US Gallon. I wouldn't call that cheap

Shift to R for "Really Efficient" mode

@thearousedeunuch

5 жыл бұрын

It can also be a Race mode, depending on the gear you were in before you select it. :) (Please don't do that.)

@HarrysDogmalaysia

5 жыл бұрын

Its going backwards

@Kyle_Godfrey111

5 жыл бұрын

O!Technology no no no.. that’s rocket mode my friend

@ralfhaggstrom9862

4 жыл бұрын

You got it ! ............

@joblessalex

4 жыл бұрын

Didn't work. My car made a loud click and jerked, then it just went into neutral. Put it back into 6th. Good thing it was a rental.

EE: Fuel Economy RX-8: We dont do that here

@brandonsanchez7465

5 жыл бұрын

Unless it has an LS

@Windows7Pro2009

4 жыл бұрын

😂🤣🤣 lmao

@melissahollandsbiggestfan5812

4 жыл бұрын

Brandon Sanchez don’t ls’ chug gas too? It’s a v8? Idk much about mpg or what good mpg is just asking

@Windows7Pro2009

4 жыл бұрын

@@melissahollandsbiggestfan5812 even the 3UR-FE is a gas guzzler.

@Jeffiekins

4 жыл бұрын

The rotary actually gets better mileage at (somewhat) higher RPM and lower load (throttle opening). At 35 mph uphill, if I use 6th gear it takes a lot of throttle (around 1500 rpm) to maintain speed and the mpg goes down to 6-9. In 4th gear, it's loafing along at 2500 rpm or so, and the mpg is at least double that. For a light car (weighs the same as a Civic), there's a really big mpg difference between uphill and level. The rule for a rotary seems to be the opposite of a piston: use whatever gear you need the least throttle to get the amount of power you want. Generally 2500 - 3200 rpm seems to give the best mileage. Above 3250, the SSV valve activates (it switches to the high-rev intake tuning) and above 4000, the 5th and 6th fuel injectors operate. FYI: at 60 mpg on level ground without wind in 6th, I get around 28-32 mpg. I did an experiment, and drove it like a Honda for a week, about half city and half highway, and got 23.4 mpg for the week. Driving a little "enthusiastically" and completely city driving (lots of sitting in traffic) brings it down to 18-19 mpg. It's a completely different beast.

Keep revs between 1500-2000 while cruising, accelerating dont let them get above 3000.... pretty basic really

@JackVinall35

4 жыл бұрын

Tamlin Giles my 6th gear is at 3000 rpm at 60mph lol, that’s the highest speed limit in my country.

@austynnegrete9113

4 жыл бұрын

Jack Vinall mine gets up there too when I’m on the highway but you cover more distance without stop lights and constant shifting through gears. So it works out to be just as efficient

@icecold8974

4 жыл бұрын

I have a Mazda 6 and it usually at 3300rpms and 50mph in 5th gear. I wondered how it keep its efficiency

@omegarugal9283

4 жыл бұрын

depends on the car, my truck cruises at 1000 rpm and shifts at 1600 rpm

@ernierobinson4892

4 жыл бұрын

I always start from 2nd gear I only first gear if im on an incline As far as shifting , I just keep my rpms as low as 1500 to 2krpms since my car has enough torque to get it moving If you're driving a car with weak torque, then you need higher rpm (a honda civic for example) vs a car with high torque (a camaro for example)

I followed the thumbnail and shifted when the fuel tank was empty.

@thearousedeunuch

5 жыл бұрын

How many mpg did you get?

@dchawk81

4 жыл бұрын

@@thearousedeunuch Eleventy.

@jchlo4790

4 жыл бұрын

@@dchawk81 😂

@stick-itproductions.3307

4 жыл бұрын

This is gold.

@FaisalBash

4 жыл бұрын

اما كذا يابو علي😂😂😂

really liked the 4 split screen with added graphics

@EngineeringExplained

5 жыл бұрын

Happy to hear it! When I put it all together and watched them side by side the first time I was so excited haha.

@ioccatonyz1

5 жыл бұрын

Very good explanation, great shifting is acquired by feel. Feel of the vehicle with feel of the road. Generally the heavier vehicles will require higher RMP's. The automatic transmission was invented for women drivers that demonstrated the lack of feel for such machines...

@richardprice5978

5 жыл бұрын

Engineering Explained thanks Jason for confirming my suspicions of a newer manual 7 or 6 speed is way more gas conservative ( @ 60mph~ ) vs a 3 speed non locking 60s automatic transmission I found that one by accident using a turbocharger calculator and reading about other peoples builds getting better mpgs I’m only part of the way through my build changes so I’m not to where I can data log and test everything 😏

@richardprice5978

5 жыл бұрын

Engineering Explained off topic but as video suggestion how much would you need / calculating for parking lot A/C or heating to work with only a battery? I tried finding it but to no avail I do have numbers for how much all of the equipment can consume @ full load in kWh but that’s different from “ just maintaining temperature deltas “ aka outside is 110F and I’m asking for less than 75F inside the car and by the way this might be a good companion video to tobitda Vinci video on Tesla model 3 battery packs specifically is it more efficient use seat heaters ( Peltier device type and efficiencies ? ) or the main cabin heat exchangers for heating / cooling or a “ cool shirt “ with a ice chest and water Plus which is faster for the job?

@owo7094

5 жыл бұрын

That 4 split screen explains everything with one picture

Yes, this is a highly detailed, well presented (a little long winded) explanation. Here's the short version; shift at as low an rpm as you can without lugging the engine. Once you've done this a few times it will become second nature to you.

@mryan4452

4 жыл бұрын

Yup common sense. Don't accelerate harshly, and keep it in fairly low rpms and not high speed, but not too low rpms so as to do damage.

@20yearsfromthepast

3 жыл бұрын

Exactly. I'm always Driving between 1.5k - 2k RPMs with my 306 GTi, but without lugging the engine. It doesn't matter how higher revs are efficient, 2k RPM is always half of 4k RPM, so it will burn fuel slowly.

@Ultrajuiced

2 жыл бұрын

@@mryan4452 However, not accelerating hashly does not mean that you shouldn't go full throttle. Some people might think that much throttle means much fuel.

@misterpotato4775

2 жыл бұрын

In a diesel car such as mine with 3.0L This is me. Everytime I change gear the only RPM where it can still move without having a vibration is more than 1.5k lower than that. It'll start to vibrate itself which isn't that great. The lower the gear the higher RPM is the time when you change your gear. As for me 1st would be around 2.2 Same goes to 2nd and 3rd 4th would be 1.8RPM All of this are the RPM when I change my gear. It'll go back to 1.5RPM which is the best spot for me. Different cars may have different RPM when to change gear. After using your car a lot of time you'll eventually know when you'll change your gear in the most efficient way possible

@jiro4559

2 жыл бұрын

Can you please describe what "lugging the engine" means in this case?

i just learned to listen to my car, i learned to drive in a manual, if you listen, the motor will tell you when the best time is to shift up, as well as shift down

@AmaanKhan-te8ll

3 жыл бұрын

When ever I listen to my car It goes braaaaaaaaaaa next gear braaaaaa

@PattyManatty

3 жыл бұрын

The right time to shift depends entirely on how you want to drive it. You can always accelerate slower and rev lower on the way up, or drive faster and rev higher. Just make sure you match your revs to the tempo you want to drive at. If you keep it revved low while applying lots of throttle you're doing lots of harm, and if you keep it revved high while applying very little throttle, you're going to get more engine drag from the revs than you're delivering to the drive train and are just throwing gas in the toilet. Of course there's a sweet spot, and you need to adapt to conditions. The more drag forces are on you, the higher you should be revving before switching as well. If the road is torn up vs a clean pave for example. Going uphill vs downhill also, of course. If you always listen for the same sound all the time you aren't adapting to conditions and probably driving poorly a lot of the time

@sdiz3430

2 жыл бұрын

Shoot .... I guess that means I have to ditch the stereo 😁

1:00 “there is roll resistance from the tires” well... you can always take them off.

@dielaughing73

4 жыл бұрын

One day...

@77thTrombone

4 жыл бұрын

Most of the rolling resistance comes from the tread. Once the tread is worn down, you give the tires another 10 psi all around, and you're off to the races, so to speak.

@CesarMartinez-wi7wc

3 жыл бұрын

I drive on 3 tires for weight reduction anyways

@juanordonezgalban2278

3 жыл бұрын

Well thar is what trains did and they do get much beter fuel economies! Just don't try and turn

@Meeper2

3 жыл бұрын

I did this and now my rotor dust cover is bent

High load low rpm = Miles per gallon High load high rpm = Smiles per gallon Edit: 1k likes?! Damn...

@EngineeringExplained

5 жыл бұрын

Haha I think you mean high load high rpm = smiles per gallon. Low load is fairly dull. :)

@Only1Sethy

5 жыл бұрын

Engineering Explained Oops! You're correct! I'll edit that! :)

@slowvag8v

5 жыл бұрын

Low load High RPM: Engine Braking

@Dubz0408

5 жыл бұрын

Granny who drives 10mph below the speed limit in the left lane had to chime in I see. "Noone should be passing me anyway im doing the speeeeed limit!" Try that on the Autobahn Gramps, get your electrolytes up... Sad...

@Only1Sethy

5 жыл бұрын

Dubz0Eight You referring to Chris Sun's comment? Idk I don't think he meant it like that, I think he meant it is unfortunate to get tickets when you're just tryin' to have a fun time (smiles per gallon) in your car. But I would agree that "gramps" hogging up the left lane is quite annoying, I see people doing that ALL the time.

What would be great to see is a comparison of mid term fuel consumption at the same distance between: 1) faster acceleration with higher rpm and immediately after reaching the desired speed, shifting into highest gear and keep it rollin (= short time of high consumption, long time of low consumption) 2) slow acceleration in higher gears to desired speed and keep it rollin (= longer time of mid fuel consumption, less time of low consumption)

@stefaneduard8169

4 жыл бұрын

A balance between the two of them would be ideal

@notanoob3920

2 жыл бұрын

Hey Guys Help mePLease I have altok10 1000cc petrol car from india ..I always used to keep 1000-1300 rpm So i thought i am theMOst intelligent person Onthis Whole universe 😅..My car is of 2013 cheap car . it dosent show fuel economy on odometre screen..So what economy i got so much years ? ..Car's 5th gear 2000 rpm is on 70km/hr speed ..why admin said 0.35 as early as possible and then said at 7.40 1500 to 3000..i Tested 2-3 times by tank to tank and it was 22Km/Litre with Ac. Company claims 25

@haraffael7821

2 жыл бұрын

In Austria you learn at driving school to keep the rpm as low as possible while driving, but speed up as fast as possible (to keep the acceleration time short).

@dinardinar2657

2 жыл бұрын

THIS IS WHAT I'M LOOKING FOR

@naturalselection4262

2 жыл бұрын

From my own experience the longer you take to get up to speed the more fuel my cars use. Shifting early prolongs fuel consumption by not benefiting from torque multiplication and spending more time loaded. I coast a lot but take off pretty fast up to speed and I average between 3-4mpg better then rated on most the cars I drive using that method.

I shift when my car asks for it, with sound.

@dchawk81

4 жыл бұрын

Q: What's it sound like when you're doing it wrong? A: Bang! And Olufsen!

@kazakukog

4 жыл бұрын

same :/

@TheBoxingNinja

4 жыл бұрын

Yeah, my car says "vom, vom, vo---- please shift me"

@Jahalang82

4 жыл бұрын

My older brother taught me how to drive manual transmission. He also taught me to shift by sound of the engine also... if it sounds like the engine is going to explode shift up, if sounds like its going to die, shift down low.

@TheEmolano

4 жыл бұрын

me too, mainly because my car don't even have a tacometer hue(in reality after driving the same car for a long time you kind of feel when you need to shift).

0:35 - “As early as possible” Okay, bye.

@Triadii

4 жыл бұрын

was going to say that haha

@Cpt.Phenom

4 жыл бұрын

Why is that?

@Cpt.Phenom

4 жыл бұрын

@Nigel Are you saying that an engine will labour less if it is routinely revved higher than needs to be?

@Maroco918

4 жыл бұрын

@@Cpt.Phenom there is sweet spot. Lugging the engine can be just as bad if not worse than high revving

@InsulinAdikt

4 жыл бұрын

@@Maroco918 I'd rather shift slightly late and burn a bit more gas than lug the engine and potentially damage it and/or the transmission.

For the best fuel economy, walking is pretty efficient.

@man0utoftime

5 жыл бұрын

Frouch Itude Mitochondria working at peak torque for the electron transport chain.

@evan8tor21

5 жыл бұрын

man out of time I almost failed my bio test don’t be so scientific now😂

@evan8tor21

5 жыл бұрын

Frouch Itude but vtec can’t kick in (yo) when you’re walking...

@JarrettWilliams99

5 жыл бұрын

Bicycling is way more efficient

@Dubz0408

5 жыл бұрын

Vitamin B12 can kick in yo with the proper fuel..

Short version, keep it low rpm between 2k and 3k at whatever gear you're in. If you pass that it's time to shift. Now if you're a racer or you want to accelerate a lot, you usually go higher rpm before shifting for power delivery bc you need to get as much juice from each gear/rev as possible, but not go too high or you'll start forcing the engine and just waste power delivery.

@Menon9767

10 ай бұрын

going above 3k in a diesel is usually unnecessary, they achieve peak torque at around 3k RPM

instructions unclear, constantly bog my engine in 5th gear up hills

@stefaneduard8169

4 жыл бұрын

Uphill = use lower gears & accelerate

@PattyManatty

3 жыл бұрын

@@stefaneduard8169 he's taking the piss out of how simplistic this video makes shifting seem, and can cause people to drive under revved

@aluisious

3 жыл бұрын

Funny, but my car goes uphill on highways in 8th gear. Just adds a little boost.

Many petrolheads I know and I'm one of them, do like to do economy driving. We have a simple system where we try to get into higher gears ASAP and keep the rpm below 3000 WITHOUT lugging the engine. I have a Honda City, which can be quite comfortable even below 2000. Infact, what we are doing is exactly what Jason says. Load it as fast as we can and keep rpm low, and NEVER ever brake (unless you relly need to, cause braking is waste of fuel). Try to coast near red lights and crossings. Blasting through highways and backroads is fun when you got loads of fuel, but can get real interesting when you are low and filling stations are far. Jason explained it engineeringly, ofcourse!! Thank you for another great video.

@ashwinmohan4503

5 жыл бұрын

Awww.. thanks buddy :-)

@TraceyAllen

5 жыл бұрын

It's too bad my MY17 impreza only has 5 gears and highway cruising speeds are right around 3000 rpm.

@ashwinmohan4503

5 жыл бұрын

Hi Tracey, that CAN be a limitation.. But 3000rpm is still pretty good, and you are definitely gonna see gains.. Rather than cruising, most fuel is wasted during stop and starts like heavy traffic. A long time back "overdrive" gear used to be installed for this very same reason. Many people thought it was for going faster, but it was to keep rpms low at highway speeds. Engineering Explained will probably do a video on it pretty soon!! Safe driving Tracey :-)

@ProDigit80

5 жыл бұрын

My Fiesta ST has 6 gears, but also cruises around 3-3,5k RPM on the highway :( If it had 2 more gears, it would cruise around 2500RPM and get 40+ MPG!

@ProDigit80

5 жыл бұрын

@Ashwin: Do you prefer engine braking over braking with a pedal?

In a nutshell: *As soon as you can without bogging*

@dj_paultuk7052

5 жыл бұрын

Yep. Pretty much how every EU taxi driver drives.

@andronclock1

5 жыл бұрын

Paul Taylor accurate.

@NishantDash

5 жыл бұрын

+Paul Indian Taxis just keep bogging lmao

@a.i.9560

5 жыл бұрын

Yeah, I remember reading that in 1981 in a "Das Auto" article about fuel economy. Old Idea that still works in most cases. EE said it right, as long as preignition does not occur.

@-Yurkey

5 жыл бұрын

Yup the short answer, shift as soon as possible. Other points would be: 1.dont accelerate while in high gear/low rpm, 3. Let go of the gas pedal while going downhill, 4. Dont use highways they ruin fuel economy...of course this advice is for granny drivers 😂😂😂

After all this engineering explained my brain is spinning at very high rpm right now.

@EngineeringExplained

5 жыл бұрын

Time to shift!

@MysteriousSamurai

5 жыл бұрын

@@EngineeringExplained Yeah, exactly :)

@jasonclegg1999

4 жыл бұрын

ikr their could of been a easier way to explain it rather than a 7 minute video

@nicholasbolton4554

4 жыл бұрын

whats good then it would be harder to understand. Sometimes it helps to pause and look/think about what was said. What made it most hard to understand (for me personally) was the pace he was speaking at. I had to pause a few times to catch up

@jasonclegg1999

4 жыл бұрын

@@nicholasbolton4554 yup i couldnt keep up, i watch youtube all the time but 4 some reason i dont seem to understand this guy most of the time

I bought a Rav4 lately. 2004 y. 2.0 petrol 4wd. Friend told me that it's thirsty, around 12L/100km or so. Well. I've driven it about a week and my average is 7,6L/100km atm. Oh yeah I did throw one rear seat away.

the red dude at 6:34 had pretty good fuel efficiency

@johncaron8608

5 жыл бұрын

Ben Goyette q

@DustinBKerensky97

5 жыл бұрын

That guy measures his fuel consumption in "miles per sandwich" instead of "miles per gallon".

@bassam_salim

5 жыл бұрын

Dustin B LOL

@SneakyB

5 жыл бұрын

Still doing enduro?

@bengoyette

5 жыл бұрын

sneakyb always!

Measurements at 58mph are an odd choice for determining "when to shift", a decision one makes when trying to get up to 58mph. I was hoping to see the differences between shifting at, say, 2500 vs 2000 vs 1500 rpm.

@philmerrifield1163

Жыл бұрын

Shift at lower rpm without it straining/stalling the engine. I drive a diesel so almost impossible to stall I can actually (on a flat road) go through the entire trans to top gear at 30mph

@mike4617

Жыл бұрын

That example was about fuel economy. The concept can be applied to determining when to shift if you’re concerned about fuel economy (shift as soon as possible without lugging engine). The test you would have liked to see would show the same thing, but would have been much more annoying for him to conduct.

I'm always amazed by how smooth your presentation is while you're driving... If I'm driving around curves, I usually stop talking or repeat myself or go "uhhh" a lot

I'm driving from 1500 to 3000 rpm in hopes that it will give good fuel economy and it turns out that it actually does thanks

When you see the smoke, it is time.

@successor5321

5 жыл бұрын

To get a new car?

@lorrainelou4449

3 жыл бұрын

😂🤣😭

7:43 that's all you need to listen to thank me later

@XyRedD3ATHxxw

3 жыл бұрын

Thank you, I didn’t have to watch the whole video for what I already know

@44actual

2 жыл бұрын

Why can’t I just thank you now? 😉

@morehn

2 жыл бұрын

I watched this a couple of weeks ago, so thank you

@Drspeiser

2 жыл бұрын

Thou art the man

@osrsfonzie1897

2 жыл бұрын

My hero

Great video, just you explaining very clearly. No music no intro, just content, I love it. Thank you !

When you own an s2000 its 9k every gear!

@cellphonelightsaber

5 жыл бұрын

Darzy NO. *slaps you with maintenance schedule* NO. *slap* NO. *slap* yes--I MEAN NO

@elanjacobs1

5 жыл бұрын

yeah it's def 9k each time. It's a Honda, it'll do it all day no problem.

@ytechnology

5 жыл бұрын

It's over 9000!!!

@noobplayer_23

5 жыл бұрын

VTEC

@tomtd

5 жыл бұрын

Certainly is.

In "ecodriving" courses, it's taught that in constant speed, use the highest gear where the engine runs well (not lugging). This is consistent with your advice. Now, another interesting question is what to do when you're at a stop light at standstill, and you're going to accelerate up to let's say 70-100km/h. Then the advice is actually to accelerate fairly hard to get up to speed quickly, so that you then can use higher gear for longer distance. You didn't touch on this at much (actually the title of this video would better have been "what gear to choose when driving at constant speed"), but I think it's an important topic. Some people think it's fuel efficient to slowly accelerate, but this just keeps them longer in lower gears which is not efficient. So the advice for best fuel economy is to put in quite a lot of throttle (probably in the 1500-3000rpm band you were talking about) to get yourself up to desired speed, and then choose the highest gear suitable for that speed. Then another thing for fuel economy is to avoid using the brakes. So coasting is important, if you see well ahead that you're going to have to reduce speed, get off the throttle early, and coast in gear. On petrol engines, this cuts off the fuel supply completely, so as you're coasting, you're using no fuel. This means from highway speeds you can get approximately a kilometer of "no-fuel-used". I see way too often people maintaining speed almost up until the stop light or whatever, and then get on the brakes. en.wikipedia.org/wiki/Energy-efficient_driving has lots of these things.

@WouterCloetens

5 жыл бұрын

Exactly. I have tested this on a petrol car, and the acceleration style you mention was measurably more efficient. Diesels seem less happy.

@OwlOfBlues

5 жыл бұрын

Yeah, my thoughts exactly when I saw this video. I always accelerate quickly in a lower gear to get up to speed and then get into highest gear (usually 50 to 100 km/h in 3rd and then immediately 6th). It takes a few seconds and a bit of fuel, unlike other people that take forever to accelerate in higher gears and shift way too early (often even below 2500rpm, with a gasoline engine!). I hate being stuck behind such people because they ruin my fuel economy as well as theirs!! :D

@vesniqui3773

5 жыл бұрын

Wouldnt that kind of driving increase the temperature too fast and put strain on the head gasket? Especially when you start driving in the morning after the car had been sitting in the cold during the night...

@swmike

5 жыл бұрын

If the engine is cold then of course you should not rev it. What we're talking about is what to do after the engine has come up to something resembling normal operating temperature. We're also not talking about flooring the accelerator, we're talking about accelerating "firmly". In most cars this would involve using perhaps 50% of the available power (for normal cars, not sports cars), typically getting up to cruising speed in 13-15 seconds perhaps. So not flooring it, not revving to redline, just get up to speed in a comfortable short time. Some people will take "forever" to get up to cruising speed, and this is not fuel efficient.

@fazecrazy6266

5 жыл бұрын

Haha that would make so much sense as to why whenever i put resume cruise control on my grand marquis (lets say was 60mph now at 40) it freaking just steps on it.

When to shift? When the car starts shaking

@maskedredstonerproz

4 жыл бұрын

or when the engine sounds like its struggling

@VivekGangwar02

3 жыл бұрын

lmao

You just answered the question i typed on youtube which was "best mpg low or high gear" perfectly. Thanks. Always love your videos.

You mentioning BSFC few videos back changed my driving style and lowered my fuel consumption some 10% more (now reaching 50mpg with 2003 3-cyl 40kw 1.2 liter gasoline). Thank you for that. While you are at it, you should mention pulse and glide driving style that is closely connected with BSFC. You need to know and understand BSFC to understand PnG. I am really happy you care about fuel economy among other things.

@EngineeringExplained

5 жыл бұрын

Awesome, very cool that you've seen an improvement in your fuel consumption!

@Pspgamer789

5 жыл бұрын

Dude, kW figures in Engines are work

@mik13ST

5 жыл бұрын

@Jay Barker If your electrical appliances are consuming power and producing no apparent work, then most of it is converted to heat. Did you know that electric heaters are 100% efficient? Assuming I have 40kW capable engine and its thermal efficiency would be 40% (which is way too high for a gasoline btw), then I could say my engine CONSUMES 100kW in fuel it is using when producing full 40kW. BSFC values are in g/kWh and if I knew the kWh hidden in one gram of gasoline, then I could calculate the thermal efficiency map from BSFC map (I guess).

@TimpBizkit

5 жыл бұрын

A kilowatt (output) is 1000 Newton force moved 1 metre in 1 second. If it required 200 Newtons (around 20kg on earth) force to push a car then 1 kilowatt would take it 5 m/s or about 11 mph. It is around 1 and a third horsepower. Obviously it will take more fuel burned because of wasted heat energy in an engine, which only converts about a quarter of the energy to force and movement (better or worse depending on load and RPM) Of course, there are different energy and power consumption that is measured in different ways. For example you could have kCal per second or BTU/second, which are defined by raising the temperature of water a kCal is raising a litre of water by 1 degree Celsius. A BTU is raising a pound weight of water by 1 degree Fahrenheit. You can in fact convert between mechanical and thermal and there are 4.1855 kilojoules (1000N 1m) in a kCal. With an audio amplifier, there will be thermal energy lost in transformers and microchips and then a set amount of electrical power delivered to the speaker. Of the electrical power delivered to the speaker, a lot will be lost in heat in the voice coil, a tiny bit lost in the cables and also some in the surround and spider of the speaker. The rest is transferred into mechanical energy in the air which is what you hear as sound, and even that becomes heat eventually when it has echoed round the room a bit and absorbed. The actual "wattage" in terms of force x distane over time of air compression is quite low (e.g. the amount of force compressing the air x the distance the air atoms moved/time to rearrange the air compared to silent still air), with even a single watt being as loud as a rock band at full bore, maybe taking as much as 100 watts from the speakers to do this. The coal burned to run the 100 watt amp might be as much as 400 watts back at the power plant, so your coal to music ratio isn't that good, although thankfully it doesn't take a lot of power to get LOUD.

@TimpBizkit

5 жыл бұрын

It's true that thermal engines are only about 25% efficient. I've heard for the bugatti veyron, its 10 radiators are to chuck out the 3000 horsepower of heat along with the 987 horsepower of smiles when accelerating full bore. We can work this out. I've heard that a bugatti veyron at max empties 100 litres of fuel in 12 minutes. Petrol is 31.5 mJ per litre so 0.1389 litres a second is 4.375 million watts which is 5864 horsepower, so a bugatti veyron is only 987/5864 = 17% efficient?? Perhaps maximum rpm is inefficient though. There might also be some unburned fuel or partially burned fuel which is inevitable. An electric heater is 100% at converting electrical power to heat. Guess what, so is a light bulb. The light gets hot, and the light that shines is absorbed by you and the furniture and turns to heat. So are most other appliances. A television has parts that get hot and heat comes out the back. The picture of the TV is light that is absorbed by the room into tiny amounts of heat. The sound of the speaker(s) is absorbed also making small amounts of heat. A kilowatt TV (which would probably fill a whole wall it would be so big) would warm the room nicely whilst you watched, and awaited your electricity bill if you watched it a lot. So if you're feeling cold, and the house is a mess, you may as well vacuum the house to make heat. The exception is a battery charger which stores energy as chemical energy, until you use the energy in the battery for more heat! If the electricity comes from a coal powerplant it is not efficient though because you are turning heat into electricity and back, delivering less than a quarter of your energy back if you count conversion and wire losses. You may as well burn something like gas to make heat because the chimney losses are less than the power plant losses by far.

I kind of always figured this was the case, but it is very cool to see the details behind it and an actual test!

@fhuber7507

5 жыл бұрын

Its too bad that he actually proved "Use the right gear for your cruise speed" and not when to shift.

@Jin88866

5 жыл бұрын

Same here, lower rpm also means less wear of the various moving parts of the engine.

Love the video, and it's always good to see someone driving with mounted cameras.

You're a great teacher man. I appreciate what you do. Keep on growing brother!

I don't even have a car, but I've watched as much of your explanatory videos as I could! really interesting stuff! thanks!

While i agree with you, there needs to be a caveat. Different engines have different power bands, Straying away from said power band too much, can ruin your mileage. I used to have a Mazda B2200 truck, 2.2 liter 5 speed, it liked to rev and averaged 25 MPG running in the 3,000-5,000 RPM power band, for acceleration. I sold that truck to my dad and he lugged it everywhere and only averaged like 18. asked me how i was hitting 25? I told him to treat it like a bike, rev it and let it run. He tossed me the keys and said, show me how you drove it. When i did, he was amazed it even got mileage, but he replicated my driving style and it instantly got 25 MPG all day every day till he got rid of it. You are right to a point, but the engine has a specific area it likes to and was designed for. if you stray too far outside that comfort zone it can hurt you both in mileage and also durability, because Spark knock is no joke, it'll ruin your engine bearings.

@mik13ST

5 жыл бұрын

Every engine has different BSFC map, but usually similar to the one Jason has shown. The best way would be to measure your own exact map using probably OBD2 data (assuming the car has OBD2 connector). It is on my personal to-do list.

Thanks for all your video. Its refreshing for someone to talk about the technical aspects of motoring. So many are simply about how quick the car is , how sporty it is. Any engineering is normally based on optimal results and a compromise of ideals. Whilst Im not a petrol head or a sports fan I appreciate others do like this and often the nest motoring research is done on race tracks. For me a car needs pragmatic. Safe and economic to run.

I was going to ask "what if you don't care about fuel economy but only want to accelerate as fast as possible?", but then you addressed that very topic in the second half of the video AND mentioned that there's a separate video dedicated entirely to that. Great video and channel!

It is written in the manual of my car, at what rpm should I shift to be fuel efficient. It actually translates into "as early as possible", as Jason said.

I don't have words to express my sincere gratitude for you bro .... Thanks a lot for spreading awareness....

I just got my first manual car, a 2013 Civic Si and this has been super helpful, thank you!

thank you for your videos, I think you are the best, I explaining the details as well.

Great video as always! Can you make a video explaining exactly what load is and how it is measured? I think I understand the idea, but I'd love to learn the details and physics behind it.

Before VTEC kicks in! Seriously though, if I hit vtec at all in my GSR, the fuel mileage would drastically decrease.

have wanted to know the answers provided by your detailed analysis for the entire time I've had my licence. Thank you so much!

With gas being $5 a gallon, I wanted to double check that I'm shifting efficiently! I didn't know this, fairly new to driving manual. Thank you!

Finally someone to answer this question. I’ve been debating this with a friend of mine for over 20 years about this. He insists that keeping the rpm as low as possible is better efficiency I always said shifting at the peak torque point is better regardless where that is in the rpm will be more efficient. Looks like i owns him a Coke

@EngineeringExplained

5 жыл бұрын

Peak torque doesn't necessarily correlate with the best BSFC, but it often is the spot with the greatest volumetric efficiency. That's intuitive, since the region where you make the most torque would likely be where you pull in the most air, relative to the size of the engine cylinders.

@spaceshipearth356

5 жыл бұрын

Kristopher Klassen I don't agree with higher gear statement. I offten get higher fuel consumption on higher gear and not accelerating, just steady right foot. It may be car specific and also different elevations lead to different results.

@Beymdoublevey

5 жыл бұрын

You're saying I need to shift at 4850rpm lol

@fuzagi

5 жыл бұрын

i used to shift at 2500 on my NA 1.6l inline-4 and it felt very sluggish and returned about 11L/KM, now im doing 10.2L/KM shifting at 3000 except on a descending stretch, where i shift at around 2200.

@miroslavdockal9468

5 жыл бұрын

Kristopher Klassen. Engine should be rev happy by apllying no more as 30% of throttle, And there comes to play in how RPM you should change gears. Engines, Cars, And gearboxes Are diferent. Nothing absolutely Universal doesnt exist. But that 30% throttle rule simply rules 😁

Thanks this was really helpful! But i have a question: Does this apply to acceleration aswell? You mentioned staying 60 MPH all the time which is quite self explaining, higher gear = lower fuel consumption, but what about accelerating to a specific speed and then shifting and holding the higher speed in the highest gear? Can you do some Tests about that too?

Thanks for the video man. Very informative. I had this bad habit of shifting gears at a very ow RPM like around 1200 RPM.

@bryanjaycinches2524

Жыл бұрын

same with my dad. the car vibrates and im bit worried about the transmission

Sorry to be unrelated but what a beautiful road. Love the videos, subbed.

If you live with LA traffic and drive manual, you are already obsessive about this subject.

@kevinnorris6558

5 жыл бұрын

Or NYC

@michaelboulos8734

5 жыл бұрын

Hahahah yess

@Uberragen21

5 жыл бұрын

Or hating the manual life in traffic.

@SD-tj5dh

5 жыл бұрын

Manual is only fun on a winding road. If I hit the highway, I use an automatic.

@tsjeriAu

5 жыл бұрын

Scott Dann If you're driving on a highway, a manual is basically an automatic. There are very few cases where you will need to downshift past 4th.

Glad you explained pumping losses as a reason for low BSFC at low loads. Obviously this only applies to petrol engines though. What about diesels? Would be nice to see a BSFC plot!

Every video is a perfect dissertation on auto mechanics; Grade A stuff!!!

Good video! I've been hypemiling. It comes naturally power or efficiency as needed!

I was just looking for a video like this! Time to save on fuel when on the daily commute & floor it in the weekends to make up for all my savings haha Right on time :)

BMW drivers didn’t like this.

@ChristinaTittu

5 жыл бұрын

Lol 🤣

@onorevolenullazzo4210

4 жыл бұрын

Why?

@averagejoe9377

4 жыл бұрын

I love comments about BMW drivers. Do you drive a BMW?

@codyehmke1218

3 жыл бұрын

Leonardo Colella car make vroom vroom noise in late/low shifts

@gabrielv.4358

Ай бұрын

Honda also

Of course this is the basis of the old "Shell Economy Run" burn and coast technique. It's amazing what can be accomplished by this. When forced to make a 350 mile trip during the 2000 fuel shortage in the UK I got just short of 50 MPG (that's an imperial gallon!) out of an E34 BMW 525i by burn and coast (and tyre pressures on the high end of the permitted range). It felt like I was peddling the thing the whole way with all the into top, boot it, into neutral work required. Going back far enough some UK cars were fitted with free-wheels in top gear to allow this to be done without all the legwork.

In my 6mt forester I noticed I can shift into 2 at 20mph, 3rd at 30 mph, 4th at 40 mph, 5th at 50 mph and 6th st 60 mph. I discovered this after plugging all my gear ratios into a spread sheet. I wanted each shift to drop the rpm to around 2000 rpm. I then noticed that each shift brought the mph to near what the gear number is.

2:48 How can you do that. Talking that complicated while driving

@EngineeringExplained

5 жыл бұрын

Haha, the '16 Crosstreks are actually rocking auto-pilot and I'm just pretending to drive. ;)

@Yathuprem

5 жыл бұрын

Haha. I knew it !!! So, the stick is a fake

@philspaghet

5 жыл бұрын

He's an engineer too lol

@InsideOfMyOwnMind

5 жыл бұрын

Yathu prem He's a videographer trying to tell a story. Not everything has to be sequential or in real time. I'm not offended by that but it amazes me how many are.

@MrBass6271

5 жыл бұрын

Cause he's smart and understands what he is "explaining"

How many trips up Bogus Basin Road while filming this video? Haha, nice job! I've always wondered about this topic.

Thanks for the great video! When would you recommend to shift if you would like to minimize the engine wear? In which rpm would you cruise?

60mph in 2nd gear would destroy my car 😂

@nathanvanpelt7216

4 жыл бұрын

What do you drive?

@JarmalK

4 жыл бұрын

@@nathanvanpelt7216 why would it destroy his car? I don't have car neither do I drive and I'm a noob

@nathanvanpelt7216

4 жыл бұрын

@@JarmalK just that a real spinny boi makes for a heckin lot of heat n rubbing. Which may shave down your cylinder wall and let the floaties hang aboot. which to your engine feels like running on a beach with sand in yer crack. Its hott components also grow thrice its size, like the grinches heart. And then stuff dont really line up as awell. But EE is a gangster and doesnt play by the rules. Gets results.

@JarmalK

4 жыл бұрын

@@nathanvanpelt7216 lol okay thanks bro ig

@CamaroAmx

4 жыл бұрын

60mph in 2nd wouldn’t destroy my Jeep, just its engine. Especially since it’s redline is 5500rpm.

Your test is kind of incomplete because you tested the coasting efficiency of each gear but didn't test the differences of efficiency to reach that speed under acceleration. If the goal is to reach a certain speed, it may be more efficient to do it quickly with less duration of load rather than slowly while being under throttle for a longer amount of time. I'd really like to know where the balance is.

@smartyman10

5 жыл бұрын

To get your car down the road the most efficiently you want to produce the power needed at the highest efficiency. It doesn't matter whether that power was used to accelerate or maintain speed. Jason makes it clear that the highest efficiency for most engines is between 1500 and 3k rpm and full load, meaning at cruising (low rpm low load) or at brisk acceleration (high rpm, high load), your efficiency is worse. Why would you want to take a long period of high efficiency and replace it with a shorter period of slightly worse efficiency followed by a period of even worse efficiency? A second good point is that accelerating faster, you have a greater tendency to 1) overshoot your desired speed, which is not advantageous for economy or 2) have to brake harder if, say, the next light turns red.

@Shakshuka69

5 жыл бұрын

@@smartyman10 you're looking at this from more of a broad physics perspective than a car physics perspective. Saying most engines are efficient between an arbitrary rev range (pretty wide one in the eg) is too much of a blanket statement. You could have two of the same exact engine running different fuel maps and ignition timing and that claim could easily be made untrue. And the coasting efficiency would end up the same after the target speed was reached, as the car would be shifted into overdrive, so it's irrelevant.

@smartyman10

5 жыл бұрын

@@Shakshuka69 , I agree, when speaking in generalities we can't be specific but I think it is important to note that the vast majority of production cars, in stock form will be most efficient at some specific speed between 1500 and 3k rpm and that above that speed they get less efficient. The exact shifting point for peak efficiency will vary by car to some degree. However, We've already established that accelerating at peak load will br more efficient than part load and if you're asking whether it will be more efficient to shift at 3k rpm or 6k rpm I would say, with very few exceptions in the automotive world, that the former will be most efficient.

@seansims2475

5 жыл бұрын

This is something I was hoping he would have touched on. While everyone is stating the engine is most efficient in low rpm high load, the vehicle is most efficient in the highest gear. So although the engine may be most efficient in any given instant running through the gears as quickly as possible it would probably be more efficient to accelerate quickly and get to the highest gear as quickly as possible. A perfect example of when this technique is likely more efficient would be something like a high way on ramp. I’m glad you brought this up and wish engineering explained had covered the concept of rush to idle because as it sits this video only discusses where the engine is most efficient and not when the vehicle is most efficient. Ironic consider he briefly acknowledges that he’s not really discussing fuel economy at the end of the video.

@smartyman10

5 жыл бұрын

Shifting as early as possible during acceleration will put you in the highest gear possible at any given time. Combine this with the fact that, typically, engines are most efficient at low rpm, then it follows that the most efficient way to accelerate is to shift as early as possible without lugging or possibly a bit later if the efficiency peak is particularly high in the RPM range.

Best economics....slow down wenn you see the police....no tickets! 👍😁

The best video out here for this topic 👍

This explains a lot more than I thought. I always just shifted off the sound of the motor or rpm rate

I remember having an up-shift timing indicator light on my 1992 Ford Tempo. It seemed based on the manifold absolute pressure that depended on the load of the engine and throttle position. Also, the 1980’s BMW’s had a needle with a L/100 Km gradation probably linked to MAF.

@drivein8055

11 ай бұрын

Not only the 1980‘s bmw, my 2007 has that, so does the 2018 BMW of my mom…

I spend 80-90% of my daily driving in 5th. Although when people decide to go 10 mph under in town, I tend to be in 3rd or 4th. My 86 gets amazing gas mileage and it's a blast to drive.

@straight2thepoint369

3 жыл бұрын

Human Being agree man best car out their

I was just trying to figure out this today!! doing some test and seeing how the car and effiency react, very intersting video. Been a fan for 3 years but now i got a car :)

Thanks for showing this, very insightful.

I usually shift below 3k rpm on a normal driving.

@vanquish421

5 жыл бұрын

Yup, that's generally correct.

@cl4ster17

5 жыл бұрын

I usually shift somewhere around 1500 rpm. Diesel life.

@95BLUERAY

5 жыл бұрын

I usually shift at 2k no more ls2 engine

@mariuszanfir2298

5 жыл бұрын

cl4ster17 Depending on the generation of diesel you're running, that might not be optimal as you may be increasing your maintenance bill in the long run. Older diesels tend to get the turbo and the air paths clogged with sooth if you are mostly out of turbo boost. Also, if you're always at low rpm, high load, your flywheel may suffer as the vibration is increased. Older diesels, such as the VW's 1.9TDI run best when shifting at ~2500 rpm. Yes, your MPG may decrease, but the amount really is insignificant. However, newer diesels are designed to run as much as possible at low RPM to reduce fuel consumption.

@MRBIGCOHONEZ

5 жыл бұрын

I shift at 2500 rpms unless I want my vetch to kick in .

When I was learning the mandatory echo driving I was instructed to accelerate as quickly as possible in low gears and skip a gear when I get to cruising speed. For example, if you are approaching an intersection you slow down as usual. Then when you are in second gear complete your turn, you quickly accelerate up to speed and go straight to 4th gear. I was told it uses up to 80% less fuel than accelerating at a normal speed and not skipping gears. I don't know if it's true or not, but it is in my muscle memory now and I still do it.

@Notov

2 жыл бұрын

if you skip to the 4th gear you dont use the 3rd, which is kinda bad cause u don't wear it out making it uneven with the gears. (hard to explain, english is not my native language sorry)

That was such a brilliant explanation!!!

You are brilliant!! Beautiful scenic road.

I drove my 1999 Honda CRV manual for over 8 years. Over time, I figured out that 2500 RPMs was the sweetspot for MPG. when I drove it, I keeped it around 2000 RPMs when going downhill and 2500 RPMs when driving Flat. It also made the car great for sharp back roads because it also has a short transmission because 2500 RPMs in fith gear is 50 MPH (which is also when it got its best fuel econmy of 28 MPG). Also, I learned if you want to get up to speed quickly for some reason, like going up a hill to merge on a highway, then you shift at 4000 RPMs. Any higher than that then your going to start buring a lot of fuel, any lower than that then you will be in fifth gear to quickly and not have enough power to get up the hill!

@frafraplanner9277

11 ай бұрын

Hondas really love to rev at 4k

Hi Jason, I've been trying all types of driving and shifting methods over the last 10 years with my 2009 Tacoma 4.0 litre and logging it. Not scientific, but over time I can see trends as well as tank specific mpg. After using this method, my last four city-only tanks of fuel have yielded 22.2 - 24.7 IMP mpg (Canadian here). Previously, I was getting 17 - 19.5 city-only IMP mpg. I previously was driving in 3rd-4th gear at 60kpm, shifting at 3000rpm and coasting at 2200 rpm and using a vacuum gauge to try and get the best mileage (as I was told that the highest vacuum numbers = best mpg). NOW, I'm shifting at 2000rpm and ending up in 5th at 60 kph with my rpm's at 1450. I'm assuming that "lugging the engine" would be any chattering or vibrating during acceleration in too high a gear? If I need to accelerate, I'll drop into 4th or 3rd. The vacuum gauge still gives high numbers, but drops more easily and quickly, with less pedal input in a higher gear as opposed to in a lower gear. Anyways, thanks for all the great content! I was posting more to confirm and illustrate to others the effectiveness of this method, rather than tell you something you already know and made a youtube video of... :) Ps, I'm lifted 3 inches and running 33's, so I'm really happy with the results, especially!!!

It's very great of you to work hard for such videos

Agree with your explanation. In fact this info is part of the basis for the new thermal cycle control mode for gasoline engines that I’ve been developing for about a decade (funding is a difficulty). Efficiency (one factor in operating economy) is improved in spark ignition ICEs by 1. Opening the throttle, 2. Increasing compression (within limits), and 3. operating “close” to peak efficiency rpm (varies but about 2500 rpm). The problem is excess power works against efficiency so engines get downsized, run too slow often, and throttled. Using new thermal cycle controls (which uses electronically controlled pneumatic valve actuators to function) these issues can be addressed so that acceleration and cruise always happen within that red band on your bsfc graph in a larger V6 or medium V8, V10, etc. REGARDLESS OF POWER OUTPUT (well, until the driver asks for more than 100 hp under acceleration). The goal is 36% thermal efficiency under most of a drive cycle (trip).

Is lower engine load and higher rpm better for the health of the engine?, of course with the engine being at the right temp & the vehicle not being red lined etc.?

So basically, I've been doing it perfectly all this time. Still great to know.

@notanoob3920

2 жыл бұрын

Hey Guys Help mePLease I have altok10 1000cc petrol car from india ..I always used to keep 1000-1300 rpm So i thought i am theMOst intelligent person Onthis Whole universe 😅..My car is of 2013 cheap car . it dosent show fuel economy on odometre screen..So what economy i got so much years ? ..Car's 5th gear 2000 rpm is on 70km/hr speed ..why admin said 0.35 as early as possible and then said at 7.40 1500 to 3000..i Tested 2-3 times by tank to tank and it was 22Km/Litre with Ac. Company claims 25

Excellent video. I have a mustang gt, so this information is extremely useful.

Experience from 40 years of driving taxi driving in Sydney, Australia. Mostly in approximately 4:0 litre, 6 cylinder, automatics. Lights change to green, give it a bit of a boot - again, a bit of a boot - then back off. The gearbox will find the highest, practical gear, by it's self. When I drove my own, Falcon GT manual, in suburban areas, I used to skip-shift a lot.

I've driven all types of vehicle with anywhere between 3 and 16 forward gears, and when I started learning, I was told to change up as early as possible, and that served me well, because it easy to tell from the behaviour of the engine if you change up too soon. I have driven automatic cars, and 40 ton dumper with an Allison 5-speed, but I much prefer manual gears. I particularly enjoyed changing gear with a crash box and judging the right revs to slide into gear without any painful grinding noises.

I drive 60 miles a day on highway and here is what I found. 1) be in max gear. 2) drive close behind semi trucks or any slow and large vehicle. driving at 54 mph (90kmh) is usually where cars have the highest MPG. BUT air resistance is taking the numbers down, thats where following trucks is important, they create a depressurisation behind them, see them as boats and try to stay in their wake. now, keep a safe distance, but keep in mind that trucks dont brake as hard as you can

@seanpaul3050

2 жыл бұрын

Yep. Anyone who has ever ridden a bicycle close behind a large bus knows. You can get up to very high speeds with no effort at all.

Excellent conscise clear elxplanation. Thank yoy

Engineer here. - when going at a constant speed, use the highest gear you can for the lowest RPM - when accelerating, use the RPM ranges that has a higher torque/RPM ratio. Look at the RPM/torque graphs of your engine (the dyno tests give you these), and select the last RPM point, where the graph is at a 45 degree increase. That will be the recommended maximum RPM.

@abdulmoez1272

4 жыл бұрын

Derively lmao engineer here

No first gear at 60mph? 😜

@thesparksplug

5 жыл бұрын

Are you crazy? Lol

@bvedant

5 жыл бұрын

thesparksplug whoooosh

@adrianharo6586

5 жыл бұрын

Redline it lol

@Banom7a

5 жыл бұрын

Reverse gear is better, you got turbo sound too

@doehetvoorgentstudent2113

5 жыл бұрын

Just put it in 'R' of race mode

I have a question that is perfect for Engineering Explained: Is it more economical to to a reasonably fast acceleration to the desired cruise speed or is it better to do it slower? The variables are interesting - the time spent accelerating being the one that springs to mind first. Hope you can make a video on this, if you haven't already. Great channel, by the way - I learn so many interesting things! :-)

@WouterCloetens

5 жыл бұрын

I experimented with this quite a bit on long daily commutes on roads with lots of traffic lights, about 15 years ago. In my petrol BMW 318i at the time, I found that quick acceleration (not flooring it, of course) to the desired speed, was more fuel efficient than long, slow acceleration at low RPM’s. All acceleration uses a lot of fuel. Doing it for a shorter time and distance is obviously better, provided that it isn’t offset by the difference in fuel consumption. I could not replicate the results with the cars I’ve had since, all diesel BMW’s.

@NicolasMedtner

5 жыл бұрын

This is my suspicion too, but it would be cool to see some data on where the line goes between too slow acceleration and too fast acceleration. It may of course depend wildly on the car. I drive a Citroën 2cv in the summers, and it has a 29 hp 2-cyl 602cc engine, and full acceleration in that is basically a normal acceleration in a normal car (or even less). Spending 2 minutes getting to cruise is not useful, and I'm going to end up at high RPMs anyway. Maybe the goal RPM range is indicative of some of the variables here. Food for an engineer's mind, or what?

@smartyman10

5 жыл бұрын

Jason basically explains it in the video, but you have to go one step further with the explanation. You want the engine to be at high load in the area of peak efficiency. For a lot of cars that's between about 1600rpm and 3000rpm. It doesn't really matter how long it takes to accelerate since the point of acceleration is to turn chemical energy in the fuel into kinetic energy in the car's mass. The only thing that tells you how efficiently that is done is: Break specific fuel consumption. It takes the same amount of energy to accelerate your car from x-mph to y-mph whether it takes a 10 seconds or 20 seconds (Let me put in right here that there is a heavy qualifier here that you are accelerating at some moderate pace at legal speeds where the amount of power accelerating the car is much greater than the amount of drag on the car, i.e. the amount needed to maintain speed, luckily, full load acceleration at 2k rpm and 5k rpm are likely within this range). Basically, the longer you can spend at the highest efficiency level, the better. Your cruising bsfc will almost definitely be worse than your accelerating bsfc, so why would you want to get to that earlier?

Modern cars have shift recommendation displays that you can use as a guide. Economical means accelerating quickly to the desired speed, shifting up as early as possible and driving with foresight. The most economical speed on the motorway is between 80 and 100 km/h (50-62 mph). Speeds over 140 km/h (over 86 mph) should be avoided because the cars consume above average fuel due to air resistance.

Wow. Ingenious take.

I don't want to have to keep paying for gas how do I download more gears so it drives for free???

@thearousedeunuch

5 жыл бұрын

Install BonziBuddy (don't do it, it's spyware).

@renoalkonga2619

4 жыл бұрын

You can just download a new car everytime

@omardude39

4 жыл бұрын

Actually most HGV drivers have three gear ranges in one gearbox, which theoretically gives them 18 gears (6 individual gears, 3 gear ratios) - but most truck drivers will jump many of them, dependent on how heavily loaded they are and what kind of incline/decline they are driving along, as many of the gears in the whole set are so similar that there's no point using them all.

@ANGEL-mb9yx

3 жыл бұрын

Fit perpetual motion machine to your car

@ANGEL-mb9yx

3 жыл бұрын

Fit a nuclear reactor to your car

I shift gear when i can't hear my radio anymore 😄.

Thank you so much for this video i'm driving cross country CA to NC tomorow.

Enjoyed your video. Can explain maximum torque & how that fits into the video you did in this post.

Gotta say, switching gears around 2500-3000 rpm always results in such a sweet low end exhaust sound. 🤪

@jahudini

Жыл бұрын

And switching from 1st gear to 3rd gear, skipping 2nd is another way to be efficient. I usually don't even use 2nd I build rpm on 1st quickly, jump to 3rd build enough to get me through 4 "faster", and I then switch to 5th and remain there till I build just sufficient rpm to get to 6th for cruise.

In a turbo engine I get a bit better gas mileage if I stay in a lower gear and not use turbo boost (air fuel mixture gets way richer once you start to lug the engine at all). So if I go up a hill in 6th I get worse gas then if I stayed at higher rpm in 4th or 5th and just stay light with the throttle

@johnmpifer

5 жыл бұрын

James Banks I wondered about this since I have a 2016 WRX 6-speed. I kinda want to do some testing to see what kind of efficiency it is capable of. But the darn thing is just too much fun to drive fast!

@kinstar

5 жыл бұрын

why would you even want to go up a hill in 6th gear lol

Very very interesting stuff. I've tried a similar MPG/speed in different gears experiment in my manual FRS, but it doesn't show engine load. Lol, not scientific, I'm not an engineer, but I'm trying to learn. Interesting about the rev range thing late in the video - I recently inherited a 97 Civic automatic (which, despite the sluggish Hondamatic, I love), and that thing often tends to shift at around 3000 rpm as well (down to like, 1700.) Very cool video as always man!

Really Good explanation, as usual...Thanks