The Best Way To Compare Car Engines - BMEP

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  • Опубликовано: 31 окт 2024

Комментарии • 2 тыс.

  • @EngineeringExplained
    @EngineeringExplained  4 года назад +635

    *Warning!* A little derivation will be involved, but it will be worth it! BMEP is fascinating! If you watch through to the end, I'm 99% sure your mind will be as blown as mine was researching for this video! Really cool stuff, like how Ford shows up Ferrari with the Mustang, how Rolls-Royce builds a head-scratcher of an engine, and if naturally aspirated engine mods are actually worth doing. Hope you enjoy!

    • @rat_king-
      @rat_king- 4 года назад +4

      Remind me why there is no correction factor for boosted/ at altitude engines? get total apples to apples comparison

    • @valentinuiliqnow6198
      @valentinuiliqnow6198 4 года назад +4

      high regards From Bulgaria, great content every time,you are my engine mentor

    • @rainhanger
      @rainhanger 4 года назад +8

      Many thanks Jason. you explained it better than my high school teacher, I finally understood that after 40 years.

    • @EngineeringExplained
      @EngineeringExplained  4 года назад +52

      @@rat_king- Unless you know the volumetric efficiency for each, there's no way to know how much air each is taking in. An engine with 15 PSI of boost has double the air of naturally aspirated engine, but if that naturally aspirated engine is operating at 120% volumetric efficiency, the engine with 15 PSI of boost actually only has 66% more air, not 100% more.

    • @destin-diesel.9495
      @destin-diesel.9495 4 года назад

      Neat.

  • @muhammadnajamuddinb.norasw7888
    @muhammadnajamuddinb.norasw7888 4 года назад +1272

    Jason lowkey flexing that his brand new miata is as cool as the LFA

    • @ralanham76
      @ralanham76 4 года назад +65

      9:20 he couldn't contain his smile

    • @EngineeringExplained
      @EngineeringExplained  4 года назад +401

      "It's basically an LFA"
      - me at the next cars & coffee

    • @hocho1717
      @hocho1717 4 года назад +30

      @@EngineeringExplained Is this the new "My s2000 is basically a Ferarri"? Now i see why you bought it.

    • @hocho1717
      @hocho1717 4 года назад +5

      @@Mexxx65 to be honest though. It actually is mine and has been for a while. When I am finished with college and have a real job, that is the car I am buying.

    • @muhammadnajamuddinb.norasw7888
      @muhammadnajamuddinb.norasw7888 4 года назад

      @@Mexxx65 Gotta shove them facts boy!

  • @Groobl
    @Groobl 4 года назад +720

    Jason is a BMEP.
    Big Math Equation Person

    • @ishkaranbrar313
      @ishkaranbrar313 4 года назад

      @@Mexxx65 ikr..

    • @j.3854
      @j.3854 4 года назад

      342.

    • @jiricech6370
      @jiricech6370 4 года назад +1

      Elementary school level of math and physics. I mean I love it but it's as simple as it gets!

    • @m.b.82
      @m.b.82 4 года назад

      @@Mexxx65 its a good comment. Big math did occur.

    • @Viages
      @Viages 4 года назад

      GFNoivern Its called Engineer, Greetings colleague Jason , Electrical and Mechanical engineer here👊

  • @HartyBiker
    @HartyBiker 4 года назад +828

    Me: "is this going to be a normal video?"
    Video starts with Jason in front of a wall of math
    Me: "ahh, just like I remember."

    • @TYFNSN
      @TYFNSN 4 года назад +3

      I feel you.
      Shitty how much physics have to work for your *brrrap*

    • @thomasa5619
      @thomasa5619 4 года назад +16

      The physics interests me MORE than the brap

    • @NoWr2Run
      @NoWr2Run 4 года назад +3

      " A WALL OF MATH " LMFAO.

    • @tlvidriss5806
      @tlvidriss5806 4 года назад +1

      @@NoWr2Run WALL OF DEATH🤣

    • @mjones2305
      @mjones2305 4 года назад

      GAY AF

  • @mmcverry44
    @mmcverry44 4 года назад +116

    "...they'll walk away from you." - You said that with conviction. You must have experience!

    • @Joe11Blue
      @Joe11Blue 4 года назад +4

      Doesn't even phase him.
      I like it.

  • @tynancravy5589
    @tynancravy5589 2 года назад +45

    Fun fact: The Cosworth DFV has a BMEP of 13.9. Quite impressive for an engine made back in 1967.

    • @dy7296
      @dy7296 2 года назад +3

      Ah yes, the Universal race engine of the 70s

  • @Kepulikeppi
    @Kepulikeppi 4 года назад +219

    The Rolls-Royce engine is most likely optimized for smooth power delivery (flat torque curve) and quiet operation.

    • @kundanbharambe4438
      @kundanbharambe4438 4 года назад +39

      Yeah! That sounds logical! Given the fact that you are driven in a Rolls not driving it.

    • @Jaymac720
      @Jaymac720 4 года назад +46

      Exactly. It’s meant for effortless and unnoticeable acceleration. It’s not meant to be super powerful like a 458. It’s meant to waft down the road without bothering its passengers

    • @boxr_4214
      @boxr_4214 4 года назад +16

      good job, you watched the part of the video where he explained exactly that.

    • @mengx94
      @mengx94 4 года назад +6

      Great that's all I came here to see debunked. Thx

    • @herpderp7114
      @herpderp7114 4 года назад +17

      Turbochargers are pretty effective as an additional muffler. Keeps engine noise down when combined with a good exhaust system.

  • @farmerpewpew
    @farmerpewpew 4 года назад +297

    "...IT BREAKS THE SCALE (that I made up)..."

    • @bruizey7319
      @bruizey7319 4 года назад +18

      I almost spat my coffee when he said that lol

    • @EngineeringExplained
      @EngineeringExplained  4 года назад +62

      That's just CRAZY!

    • @bruizey7319
      @bruizey7319 4 года назад +9

      @@EngineeringExplained I chuckled because it's just so... you!

    • @iplaysdrums
      @iplaysdrums 4 года назад +1

      Bruizey It really is very characteristic of Jason, particularly the delivery!

  • @JohnSmith-sx2fh
    @JohnSmith-sx2fh 4 года назад +26

    At 120% of natural air pressure you’re looking at nearly 3 lbs of boost with an intake, this is very impressive!

  • @TheNoopinator
    @TheNoopinator 4 года назад +38

    I would really be interested in a video about BMEP calculations for rotary engines. I know they dont have many "similar engines" to compare with, but it interests me nontheless. Great video as always :)

  • @ThungStudios
    @ThungStudios 4 года назад +436

    "only compare similar vehicles!"
    > compares the mitsubishi mirage with the ferrari 458
    haha very cool video

    • @m.morininvestor9920
      @m.morininvestor9920 4 года назад

      😅

    • @m.morininvestor9920
      @m.morininvestor9920 4 года назад +10

      I actually used a Toyota Echo for pulling a tree once 😅 it worked

    • @user-qx7tm5df8j
      @user-qx7tm5df8j 4 года назад +8

      @@m.morininvestor9920 prithee allow me to bethink about thy actions...
      its not smart to pull a tree with a car... also "tree" could mean anything.

    • @ody2cuffs508
      @ody2cuffs508 4 года назад

      Use

    • @ody2cuffs508
      @ody2cuffs508 4 года назад

      Use d

  • @thatoneotherotherguy
    @thatoneotherotherguy 4 года назад +119

    15:30 "Let's say this is a 2.0L engine we're modifying". Gee, I wonder why? ;)

    • @horstgunther9521
      @horstgunther9521 4 года назад

      I am too lazy to do it and maybe I lack some of the variables but I would really like to know the BMEP of the m133 2l 4zyl Engine in my A45 with 381Hp would have. And more so the new m139 with 2l in the current A45 at 420HP..

  • @SeanBZA
    @SeanBZA 4 года назад +115

    To be fair to Rolls, they want that engine to be as quiet as possible, and to last at least 10 years without needing an overhaul, while the Ferrari is likely to not make the distance, and in general will not be a daily use car like the Rolls. Thus run the engine in a lower stress region, but have the turbo small to maker it accelerate fast off the mark, giving the impression desired of "effortless power", the exact opposite of the Ferrari, which is meant to be heard.

    • @tommihommi1
      @tommihommi1 4 года назад +29

      the engine is also designed to have a very flat power curve over the rev range, to make it feel smoother

    • @eknaap8800
      @eknaap8800 4 года назад

      You're absolutely right. 👌

    • @eknaap8800
      @eknaap8800 4 года назад

      @@tommihommi1 Also true. 👌

    • @iridium130m
      @iridium130m 4 года назад

      Great point on reliability. The topfuel dragster engine can only go 1/4 mile between rebuilds to achieve its number.

    • @mariuszanfir2298
      @mariuszanfir2298 4 года назад +6

      @Nabil Sabli "Thats how impressive rolls engine is in terms of refinement" You mean "BMW engine", right? :)

  • @lesliethilow3011
    @lesliethilow3011 3 года назад +3

    This is one of your best physics lessons in my view. I’m an earth science teacher who enjoys watching other great teachers teach. I’ve also enjoyed working on, maintaining and analyzing engines, airplanes, cars and motorcycles since I was a child, the offspring of an engineering wizard. So I like the topics you discuss. You have a great teaching style. I hope you keep this kind of thing up for years to come. We need more teachers like you who can inspire as well as enlighten!

  • @CapnT87
    @CapnT87 4 года назад +45

    Ha, I haven’t seen BMEP calculations since my ICE course in Mech Engineering 🤓🤓. Wünderbar

  • @TGT_86
    @TGT_86 4 года назад +214

    Someone: hey my Ferrari V8 is amazing
    Jason: (takes out a whiteboard)

    • @kj-marslander
      @kj-marslander 4 года назад +4

      nice. I'd sit and listen.

    • @davidstepan8490
      @davidstepan8490 4 года назад +11

      Actually, the V8 458 IS amazing.. It's the V12 that isn't (as much)

    • @nik7bkh965
      @nik7bkh965 4 года назад +8

      @@davidstepan8490 The Ferrari V12 is one of the most amazing engines out there right now. Who wants to live in a world where every car is a small turbo 4 cyl with 2000ccm or even worse: only electric cars.
      Be glad for the variety.

    • @MaxxerG
      @MaxxerG 4 года назад +6

      @@nik7bkh965 who would want to live in a world with no air microparticle pollution

    • @CalgarGTX
      @CalgarGTX 4 года назад +6

      @@MaxxerG I know right, I'll keep my freedom to get lung cancer and other respiratory problems, and brain damaged kids thank you very much

  • @willmarks4541
    @willmarks4541 4 года назад +81

    Can you make an online university just for car stuff like this. Right now with isolation and everything. I would be the first student. Great vid as always ! Up the Mazda with the 12.6 !!

    • @EngineeringExplained
      @EngineeringExplained  4 года назад +73

      Here you go! ruclips.net/user/engineeringexplained

    • @cody4478
      @cody4478 4 года назад +12

      Bosch Automotive Handbook. You're welcome

    • @olegkolesnikov7155
      @olegkolesnikov7155 4 года назад +3

      @@EngineeringExplained Speaking of the Mazda, I'm surprised you didn't find the BMEP of the 2019 and later models. The tuning has been quite significantly revamped, or so I've heard. The power figures match that statement, too, with a pretty significant increase for such a small displacement. And yeah, I know the 2016 is the model you own, but come on, that thing basically copy pasta'd the Mazda 3 engine.
      Edit: just searched it up, and yeah, the 2019 model saw an increase in almost 30hp which is like 20%, insane!

    • @tzikis.
      @tzikis. 4 года назад +4

      @@EngineeringExplained iiiii see what you did there!

    • @k1114da1
      @k1114da1 4 года назад +4

      @@olegkolesnikov7155 It's 12.9

  • @jacob50384
    @jacob50384 4 года назад +130

    I'm going to be so cool at parties. Too bad we're in quarantine and my dogs don't understand anything other than if they sit long enough they get peanut butter.

    • @savagetuner2404
      @savagetuner2404 4 года назад

      Jacob Wagner what the hell does this comment have to do with this video? Go like farming elsewhere

    • @nielsonderbeke8507
      @nielsonderbeke8507 4 года назад +6

      My BMEP is bigger than yours

    • @jasonmoser7287
      @jasonmoser7287 4 года назад +2

      I bet they get the peanutbutter. 😉😉😉😉

    • @787brx8
      @787brx8 4 года назад

      The kitty gets the milkshake and the bunny gets the pan...cake!

    • @RRSmurf
      @RRSmurf 4 года назад

      @D.O.A. 🤣

  • @traviskellogg66
    @traviskellogg66 4 года назад +248

    If I was back in high school with him as my teacher making these equations relevant to my interests then I would of been an A+ student

    • @j.m.7907
      @j.m.7907 4 года назад +8

      That's your fault that you didn't find the beauty in math/physics, not your teachers lol. You were, at least then, just Naive. Anything you could imagine, can be explained by math/physics/chemistry. Nothing has been created by accident. It's a beautiful thing when you start to realize how things work isn't it!

    • @Invisifly2
      @Invisifly2 4 года назад +20

      @@j.m.7907 Teachers rarely do anything to incentivize such discovery with math though. Math is extraordinarily dry for most without some practical applications to tie it to.

    • @ytmB4HyU4kUq
      @ytmB4HyU4kUq 4 года назад

      You're right about what you said. But the biggest issue is actually our education system. If they want most if not all children to succeed in school, then they need to be teaching us in ways that will cater to our interests and strengths. You can't have an education system where only some people will succeed and others won't, that's a flawed system. Unfortunately, that is the reality and it's sad that we pay taxes to a flawed education system.

    • @TeiwazTheGoat
      @TeiwazTheGoat 4 года назад +11

      JOEY M You’d be an awful teacher with that attitude. Literally every science educator out there would disagree with you.

    • @gsxerwhite
      @gsxerwhite 4 года назад +4

      Joel West I took a physics 101 type class and the professor made it fun by showing practical applications that everyone could relate to. Way better than any science class I had in high school. I actually looked forward to that class.

  • @mishalharbi777
    @mishalharbi777 4 года назад +9

    The joy of learning how it all works. I love "Engineering" when it is "Explained". Thanks Jason for a great video as usual.

  • @ejemg3183
    @ejemg3183 4 года назад +40

    Basically:
    BMEP (bars) * 8 = Torque from 1 liter displacemant [4 stroke engine]
    BMEP (bars) * 16 = Torque from 1 liter displacemant [2 stroke engine]
    for US:
    BMEP (psi) * 0.544 / 61 = Torque from 1 cu inch displacemant [4 stroke engine]
    POWER:
    Torque (NM) * RPM * 0.104 / 735 = Power (PS)
    Torque (lb-ft) * RPM * 0.142 / 745 = Power (HP)

  • @fatalgaming6068
    @fatalgaming6068 4 года назад +119

    Jason basically speaking gibberish the entire time:
    Me: Yes, I completely understand

    • @kj-marslander
      @kj-marslander 4 года назад +5

      lmao, I don't even have to watch the video to figure out that I'm not gonna understand anything. But I watch it anyways cause it makes me feel like I know about cars.

    • @davisbyer4791
      @davisbyer4791 4 года назад +2

      As my professor used to say "IT'S ALL ABOUT THE UNITS"

    • @ervinm.5065
      @ervinm.5065 4 года назад +3

      Problem is I understand, I really do, but chugging down all those informations in 16 minutes is hard so I forget everything a the end. His whiteboards are between 1 and 2 hours of physics class

    • @sepg5084
      @sepg5084 4 года назад +3

      if this is gibberish to you, you might need to go back to highschool

    • @demonsamongstmen562
      @demonsamongstmen562 4 года назад

      ME RIGHT NOW

  • @DanLMH
    @DanLMH 4 года назад +141

    "Spreadsheets Heck Yeah!"
    take my thumbs up EE :p

  • @Wolfiecolada
    @Wolfiecolada 4 года назад +54

    "it breaks the scale -- that i made up" sums up my life

    • @fricardo3
      @fricardo3 3 года назад

      You meant to say it sums up your eating habits?

  • @Somethingisntright64
    @Somethingisntright64 4 года назад +1

    I’m glad there’s another smart person out there thinking in engineering terms. Years ago, when I talked like this in my engine building class I got that “deer in the headlight” look from the instructor. Thanks for a great video. Now onto compression ratio, quench area and L/D intake valve calculations. Yes!

  • @hh8578
    @hh8578 4 года назад +12

    I think these videos are very useful, especially for us mech engineering and automotive students, but you make it easy to understand even for other people. Keep doing this good work

  • @tazjam12
    @tazjam12 4 года назад +105

    "But think of how much more interesting people will find you at parties when you say words like 'Brake Mean Effective Pressure' instead of 'torque'... they'll walk away from you"
    You mean "Keep their social distance".
    Also... how are you having parties?

    • @MrJef06
      @MrJef06 4 года назад

      Most people will likely walk away when you say 'torque' anyways 😉

  • @ZulReviews
    @ZulReviews 4 года назад +9

    Perfect timing ! Just today I was looking for this info because found out bmep are always there on every engine spec sheet. Now I know, thank you !

  • @jaytroxel3495
    @jaytroxel3495 4 года назад +1

    Engineering Explained... is really the perfect name for this channel. I've learned so MUCH cool stuff on here! Thanks Jason for continuing to come up with fantastic video content, and making it INTERESTING. Stay safe amigo!

  • @isaks3243
    @isaks3243 3 года назад +1

    I did some calculations on my 1973 volvo p1800es and it turns out that it has a surprisingly good bmep of 12.15 bar. that got to be really good for a small displacement inline 4 from the 70s
    and you're wrong. the best sports car ever made is the volvo p1800. it is the best looking if you ask me, it is raw, sounds great, drives great, pretty quick and since there is absolutely nothing helping you driving the thing, not even power steering do you get the purest road feel of any steering method.

  • @shaunnyman4140
    @shaunnyman4140 4 года назад +90

    He's literally the only person on RUclips who is capable of proving an MX-5 is just as good as an LFA.

    • @ScootersMum1
      @ScootersMum1 4 года назад +3

      yeah because an mx5 does 0-60 in 3.6s huh. LOL

    • @soundseeker63
      @soundseeker63 4 года назад +2

      Just as good in one specific metric that nobody ever heard of and means little in the real world, yeah :-D

    • @wolfemancola
      @wolfemancola 4 года назад

      Proving? i think you mean pretending

    • @JakobusVdL
      @JakobusVdL 4 года назад

      Its pretty much self evident, but the maths help ;-)

    • @JakobusVdL
      @JakobusVdL 4 года назад

      @@soundseeker63 when you say 'no one's ever heard of' you mean apart from all those mechanical engineers who use this daily?

  • @BiggMo
    @BiggMo 4 года назад +51

    Love cars, hate math - Jason is like my paradox emulsifier

    • @kj-marslander
      @kj-marslander 4 года назад +1

      Think of it like this, who do you want to teach you math, an old college teacher that doesn't care about real world scenarios, or this guy, comparing everything to car engines? This guy wins hands down. But then again, I don't hate math that much.

    • @BiggMo
      @BiggMo 4 года назад

      Karam J: Amen - if I’d had a teacher like him back in the day, maybe I wouldn’t hate math. (Of course that would had been before he was born) - I’m thankful for guys like him.

    • @foadrightnow5725
      @foadrightnow5725 4 года назад +1

      Big Mo - Paradox emulsifier? Now that's a great term! I'm going to use it at parties! That, and BMEP. Cheers!

    • @OmicronChan
      @OmicronChan 4 года назад

      @@BiggMo Nothing is stopping you from rediscovering the wonders of maths now.

  • @kylewolf1052
    @kylewolf1052 4 года назад +7

    Send out the spreadsheet so we can calc our BMEP!! Great video!

    • @danieldimitri6133
      @danieldimitri6133 4 года назад +1

      It's torque/displacement with a unit conversion to make it a pressure unit. You can write a long looking equation to convert to work then to the pressure it would take for that volume per rotation which might seem easy in metric because it's a very base 10 system. However metric also make distinctions between force, mass, and weight and newton's take earths acceleration of gravity into account and the rotational nature of torque measurement means a pi is involved. Imperial units aren't any better as the unit for torque and work are sometimes expressed the same way and there are coefficients on practically every unit conversion. To avoid making errors I'll just write down some conversion factors below. Maybe that doesn't break it down but for comparison purposes between engines you can get an idea. Normally aspirated engines can be compared easily and it says a lot about how well they are tuned. Boosted engines have a bigger challenge with heat management and might also make a different decision about the engines ve vs the boost used and other things. You can make dozens of comparisons between the same 2 engines normalizing for different factors but how you weight them in your mind as important is somewhat arbitrary.
      For nm/l to bar it should be nm torque/litter displacement * 0.12566 = bar bmep
      Bar to kpa is bar * 100 = kpa to express it in kpa
      Lb-ft/In³ (foot pound per cubic inch) to psi bmep is lb-ft torque ÷ cubic inches * 148 = psi
      Psi to bar is psi * 0.0689

  • @jakemalinowski1397
    @jakemalinowski1397 4 года назад

    It is nice to watch a RUclips video that does not bore me with incompetence. Thank you for all the work you put into developing your videos.

  • @MonsterNewfie
    @MonsterNewfie 4 года назад +2

    I did this calculation on a 82 normally aspirated 2.8L Diesel Datsun 810 Maxima and compared it to my 09 BMW 335I 3.0L twin turbo. The difference was amazing. I thought that the 80hp old diesel engine was bulletproof because of the nature of being a diesel. But it had such a low BMEP that the engine was never under much stress.

  • @slolx50
    @slolx50 4 года назад +4

    Thanks for taking me back 20 years to my IC Engines class!

  • @JakeSkellington1
    @JakeSkellington1 4 года назад +111

    If my math teacher in highschool used cars as a way to teach equations, I would have passed every class with an A+.

    • @lordflufffluff
      @lordflufffluff 4 года назад

      @B
      (Estimated Seeds per watermelon * 10) -(estimated seeds per watermelon * 4) ≈ number of seeds

    • @lordflufffluff
      @lordflufffluff 4 года назад

      @B
      I can't figure it out.
      Is there a way to write an expression for that?

    • @veneratedmortal4369
      @veneratedmortal4369 4 года назад

      Ahh the old trick question, where knowing math is irrelevant but being good at English is.

    • @drealist7941
      @drealist7941 4 года назад

      My answer 0 I only eat seedless water 🍉

    • @BLMCFR
      @BLMCFR 4 года назад +1

      And that's why I did get straight A's in math - not because the teacher used automotive as the example, but I turned every example into an automotive, railroad, or machinery example!! Geometry and math were fun and I could understand the formulas in detail!!

  • @Flies2FLL
    @Flies2FLL 4 года назад +8

    Great video! Two things come to mind:
    1. The power stroke does not end at bottom dead center, it ends when the exhaust valve opens. This typically happens at 120-125 degrees after the piston reaches top dead center, so for the 55-60 degrees remaining after the valve opens, the cylinder pressure is effectively zero. I guess that BMEP means the average pressure over the 180 degrees from top to bottom, despite there being no pressure for those 55-60 degrees?
    2. Two engines with the same BMEP, the same displacement, and the same RPM can have quite different mid range torque and thus power. If one of them has a very long connecting rod and the other a short connecting rod, the long rod engine's piston will "dwell" for a longer period near the top of the cylinder while combustion is taking place, thus developing far more pressure than the short rod engine, and it will have way more power in the middle of the RPM band. Why? Draw this out on a piece of paper and you will see why. Draw a crankshaft throw and a connecting rod/piston that is long and another one that has the same stroke but a rod half as long. Imaginarily move the long rod's crankshaft 15 degrees or so and see how far down the piston moves. Now, do the same thing with the short rod drawing- You will see with the short rod the piston moves FAR MORE than with the long rod. Since the exhaust valve opens typically while the mixture is still burning, the dwell period of the long rod design allows more of the charge to be burned before this happens which produces the same BMEP but with more actual torque and power for the long rod design.
    Jason, you ought to do a video about this effect. Volkswagen used very long rods in the VR6 engine just for this reason.

    • @kennethalbert4653
      @kennethalbert4653 4 года назад +3

      Ha! Smokey Yunik said "stuff in the longest damn rod you can"!

    • @crxtodd16
      @crxtodd16 4 года назад +1

      Agreed - rod/stroke ratio is pretty dang cool, and I'm sure there is a lot more I could learn about it.

    • @trungson6604
      @trungson6604 4 года назад +3

      Sorry, item #2 is not true. By definition, if two engines have the same BMEP , same displacement, and the same RPM, then they will produce exactly the same power. This is by definition and is not subjected to any variation in other engine parameters.
      Now, WRT long connecting rod, you will have higher dwell time at TDC, and you will have higher heat loss to the engine's combustion chamber at lower rpm, when there is already plenty of time for the fuel to combust, higher propensity for detonation that you may have to reduce compression ratio, thus reducing top-end power and torque...so low-end torque will suffer, in exchange for may be higher top-end power when there will be more time for combustion at top-end RPM, but, you must reduce compression ratio, which will affect top-end power. Furthermore, longer connecting rod will make your engine more bulky, heavier, and higher reciprocating mass due to the higher weight of the con rod, which will require beefier bearings and pins...that may affect top-end RPM...engineering is the art of making compromises.

    • @SidneyCritic
      @SidneyCritic 4 года назад

      @@kennethalbert4653 That's not right. Prostrock will run a shorter rod than optimum so they can use a lower deck height and straighten the inlet port to the manifold. Basically you are relying in atm pressure to fill the cyl so it has priority, ie, a higher magnitude of importance, than small effects like rod length. In 2007 a 500cu Prostock was making about 1500hp@10,750, so at 3hp/cu NA they must be doing something right. lol.

    • @SidneyCritic
      @SidneyCritic 4 года назад +1

      BMEP is an average, ie, more initial and less latter evens out.
      Port velocity has more of an effect in making torque then rod length. With a 2-valve engine we make max TQ when inlet port is designed to run at port velocity of 500-550ft/sec. NA engines are limited to a airspeed of 0.6mach(700ft/sec) before they go into sonic choke and stop producing power. If you want to see the influence of ports look at the LS1. It has a cam with an operation range of 3500rpm, but the engine will rev to double that because the port hits 700ft/sec at 7500rpm. The myth that a long stroke engine makes more torque because of the stroke is wrong. It makes more TQ down low because it has a small bore that only fits small valves and small ports, and this means the port hits it's velocity limit at a low rpm.

  • @TheSuperDeuce29
    @TheSuperDeuce29 4 года назад

    I have to say first how much I enjoy your videos. Your ability to use equations to describe your point is impressive. I was fascinated as well when I learned that engineers were able to get over 100% efficiency out of a naturally aspirated engine. One thing I noticed you neglected to mention in that is how important valve timing, overlap, and size play a roll in both air velocity and pressure. They use the exhaust valves scavenging effect to draw fresh air in like a vacuum during the overlap to maintain air speed. Also why the ratio of the intake valve to exhaust valve size can be so critical. Again hats off to you for super fun content. Thank you.

  • @vincentlb4562
    @vincentlb4562 4 года назад

    I'm student in internal combustion engine your videos are great to learn my class in another languages TY

  • @joshp2542
    @joshp2542 4 года назад +5

    I think some people refuse to believe that for a daily driven car, top end power isn't as important as how the power builds up and how the car handles. Too many people think that they drive at redline 100% of the time and forget about things like torque and power to weight ratio.

  • @chandreshverma6419
    @chandreshverma6419 4 года назад +12

    Tuning your car up to double the horsepower it can make naturally
    That's why he named the spreadsheet Heck Yeah!!!
    👍👍👍👍👍☺

  • @sonicseaweed
    @sonicseaweed 4 года назад +35

    Oooooh, more tools for my social distancing toolbox

  • @fivish
    @fivish 4 года назад

    So refreshing to see sums without any calculus. makes it so much easier to understand.

  • @andreas.abrahamsson
    @andreas.abrahamsson 4 года назад +1

    Brilliant video. Never has physics/mechanics/mathematics been so much fun and easy to understand! :)

  • @gusgiesel
    @gusgiesel 4 года назад +10

    8:58 "... extraordinarily expensive and super fast." LOL I love how you are working the geeky sense of humor into the videos. Thanks for another great video.

  • @antnyneveruploads
    @antnyneveruploads 4 года назад +41

    Can I get the spreadsheet you used to calculate every car's BMEP? Asking for a friend.

  • @ChrisMuncy
    @ChrisMuncy 4 года назад +30

    LOL this just boils down to you trying to cost justify putting a supercharger on the new Miata :p

  • @kyleerickson8691
    @kyleerickson8691 4 года назад

    I needed you as an algebra teacher. Engines are way easier to understand than random problems

  • @kawaiikeyboards
    @kawaiikeyboards 4 года назад

    as a person who studied both advanced mathematics and graduated from an automotive college I appreciate the effort you came up with equation to calculate BMAP. Also why a Rolls Royce V12 Twin Turbo has a less effective BMAP is simply because it was never meant to be a race engine and was based on an old design meant more for comfort and low end torque.
    However the 458 engine is a work of art. No surprise it won several award for best performance engine, highest HP per liter and also one of the highest revving engines on the market at the time. All of it being beaten by the Aston Valkyrie, but even so the 458 is still a mass produced sports car with all the warranties and probably doesn't need be rebuild every 50/100ks like most hypercars. Shows how much NA engines has evolved over time.

  • @AntonioBarba_TheKaneB
    @AntonioBarba_TheKaneB 4 года назад +11

    please include motorcycle engines in your videos, they have impressive power for their displacement (200 HP per Liter is not uncommon for street legal bikes). For example the 2019 Suzuki GSX-R1000R has a BMEP of 14.83

    • @mateuszbarya9098
      @mateuszbarya9098 4 года назад

      my 1998 r1 have BMPE of 13.8230076758

    • @SundbyCPH
      @SundbyCPH 4 года назад +1

      My 97 Honda cbr 600 f3 with 66 nm has 13,85 and my 84 gpz 900 r with 85 nm has 11,65. Engine efficiency and design improved a lot between 1984 and 1997! In motorcycles you also see the same engines being tuned for torque in road and touring versions and hp in race versions.

    • @brianmichael316
      @brianmichael316 4 года назад

      My 2015 bmw f800gt BMEP=13.5, and can get around 60mpg. Well done BMW.

    • @seanathanq
      @seanathanq 4 года назад

      I was wondering about bikes, thanks

  • @danmyers2338
    @danmyers2338 4 года назад +8

    This was a really good video chocked full of interesting information and presented very understandably. Just one question, though: For distance you used the stroke, or the distance the piston travels in one half a revolution during the power stroke. For the time, you used the revolutions per second divided by 2 since the power comes only every other revolution. But, that’s the entire revolution, and the power stroke is only half a revolution, so shouldn’t you divide by 2 again, or rev/sec/4, to get the actual time the piston takes to travel the power stroke? (And for a 2-stroke engine, you would divide by 2. ) That would make MEP = 8 * Torque * RPS / Vd, or twice what was presented.

    • @A-FrameWedge
      @A-FrameWedge 4 года назад

      No.

    • @robostory1711
      @robostory1711 4 года назад

      That actually makes sense. Should be divided by 4 for a 4 stroke and by 2 for a 2 stroke.

  • @rogerio1234rogerio
    @rogerio1234rogerio 4 года назад +4

    Hi, Jason. You forgot to mention your BMEP of your previous sport(ier) car. The F20c from the HONDA S2000 has a BMEP=13.1. And that's on a 20+ year old design!
    Take that, Miata!

    • @gigagdragoon2345
      @gigagdragoon2345 4 года назад

      Too bad it weighs an extra 500 lbs..

    • @stancarole
      @stancarole 4 года назад

      My Miata develops usable torque over the driving and racing range. I can start smoothly in third gear and race with the standard gearbox

  • @gavronsky
    @gavronsky 4 года назад +1

    @Jason There is another way how do I compare engines (actually very similar to yours but a bit more convenient from my point of view). Here is my statement: Well engineered gas NA engine can produce 100 Nm of torque from a 1 L
    Mazda 6 Skyactiv-G -2.5L 258 Nm - perfect engine
    Toyota Camry V6 3.5L 357 Nm - perfect engine
    Chev Epica 2.0L 192 Nm - very good engine
    Toyota Carina E (1996) 1.6L 141Nm - just good
    You even can compare Turbocharged and NA engines in this manner. For example my Honda Accord 2.0T has 370Nm, so it is more or less equal to well engineered 3.7L NA engine. And it is, as 2.0T is a bit faster than 3.5 L NA from previous generation

  • @albertobrancati
    @albertobrancati 4 года назад +1

    yours videos are always great, but man this is just amazing!!

  • @Slaktrax
    @Slaktrax Год назад +8

    I found a formula sometime ago that used the maximum torque the engine made in lb/ft, multiplied by 2473 then divided by the cubic capacity. e.g. 425(lbs/ft) x 2473 / 5665(c.c.) = 185psi [~200psi being about the upper limit for N/A engines]

    • @benjaminwiner6220
      @benjaminwiner6220 10 месяцев назад

      Excellent

    • @stevecummins324
      @stevecummins324 9 месяцев назад

      The constant 2473, will come about as the result of multiplying an assumed rpm(that of an average rpm for peak torque?)
      by the necessary unit conversion constants.
      Thus the formula will estimate on the high side for engines that make peak torque at lower than the assumed rpm. And estimate lower thsn true BMEPs for engines that make peak torque at higher than average RPM.

  • @NotSoHandyCarGuy
    @NotSoHandyCarGuy 4 года назад +28

    Love the videos, Jason. The math is way above me, but I like to pretend I understand everything you’re saying 😂. It makes me feel smarter

    • @merlinevseichik9479
      @merlinevseichik9479 4 года назад +5

      One of the reasons i like his videos, he actually explains the math pretty well, so that anyone could do it pretty much.

    • @nielsonderbeke8507
      @nielsonderbeke8507 4 года назад +1

      @@merlinevseichik9479 that's the definition of a good teacher!

    • @danhard8440
      @danhard8440 4 года назад +1

      you took the words right out of my mouth that's also why I watch BigCliveDotCom lol

  • @jackharvin4586
    @jackharvin4586 4 года назад

    I'm a Lab Tech...I worked in the Knock Lab for about 10 years. We ran the 3C engine to rate 100 ll Aviation fuel. We used B.M.E.P. and F.M.E.P. and I.M.E.P. to do our calculation for an Aviation fuels Octane rating. The 3C rating is the A.S.T.M. standard for Aviation fuel octane rating as well as the Lean rating on a M.O.N. engine. Same engines 3C is forced induction and M.O.N. is naturally aspirated

  • @danacook9615
    @danacook9615 4 года назад +1

    when I was in school studying aircraft engines we always did a horsepower per specific fuel consumption to compare engines. I think that would be interesting to do here.

  • @lucioswitch
    @lucioswitch 4 года назад +26

    It would be interesting to see the value of some motorbike engine. Just for comparison.

    • @dernachtmannkommt
      @dernachtmannkommt 4 года назад +16

      Lucio Switch naturally aspirated:
      BMW HP4 race: 15.1bar
      Aprilia RSV4: 14.7bar
      Kawasaki ZX10R: 14.5bar
      CBR 1000rr: 14.3bar
      BMW S1000rr: 14.2bar
      Yamaha R1: 14.2bar
      Ducati Panigale v4: 14.1bar
      Supercharged:
      Kawasaki H2R: 20.8bar (Boost: 1.4bar gauge) equivalent NA: 8.7bar

    • @AanjE
      @AanjE 4 года назад +1

      @@dernachtmannkommt Lets not forget the Brutale 1000rr 14.6 its a lot more comfortable to ride than superbikes ;) well until you going over 180 then you really miss having a fairing.

    • @John-nd7il
      @John-nd7il 4 года назад +1

      Usually lower but much higher rpms

    • @JakobusVdL
      @JakobusVdL 4 года назад

      Thanks@@dernachtmannkommt, so up towards the top end of the scale. But able to rev much higher than even high performance larger capacity car engines

    • @A-FrameWedge
      @A-FrameWedge 4 года назад

      @@AanjE I think you will miss the fairing way before 180 mph more like 100 mph

  • @John-md3ld
    @John-md3ld 4 года назад +33

    I was playing this video in full screen and my siblings thought this was an algebra lecture........

  • @TrueSkyl1n3
    @TrueSkyl1n3 4 года назад +34

    There was me about to go “Woooahh my little Skoda is about 15 on that scale”... before I remembered it’s both Turbocharged and Supercharged 🤣

    • @basstard13
      @basstard13 4 года назад +3

      Love those twin charge engines! How is it going?

    • @tojiroh
      @tojiroh 4 года назад +3

      a twin charged Skoda? WTF.
      *3.5 seconds of Google Fu later*
      As yes, the wonderful VW 1.4 TSI.

    • @baileycocks
      @baileycocks 4 года назад

      Andy Fisher 2.3 seconds 0-gulag

    • @georgeioannou5675
      @georgeioannou5675 4 года назад

      Skoda felicia fun 1999= 10.6 bar

    • @razmann4k
      @razmann4k 4 года назад

      My 2001 Renault Clio 1.4 8v is only a 10.1 on the scale :(
      Too bad this engine doesn't have a large aftermarket, or at least that I know of.

  • @Jpk516
    @Jpk516 4 года назад

    So I saw the notification for this video while procrastinating on my Physics homework. Somehow you explained my physics homework better than my teacher could, and made it enjoyable too. Your videos are awesome, keep up the great content!!

  • @HorrorbleGamer
    @HorrorbleGamer 4 года назад

    Wow dude, everything single video you release is an eye opener.

  • @morthomer5804
    @morthomer5804 4 года назад +19

    Ah haha... "more interesting at parties " ... like my future wife's reaction when I said "g-force." 😆

  • @arjunyg4655
    @arjunyg4655 4 года назад +26

    Wondering where an S2000 would land, but I don’t wanna convert units lmao.

    • @bradkerr2798
      @bradkerr2798 4 года назад +9

      F20C: 13.1 bar, F22C1: 12.8 bar. Slight variation depending exactly which torque rating (used 153 and 162 lb-ft).

    • @joshp2542
      @joshp2542 4 года назад +3

      The s2000 would land in the puddle of oil the thing leaks and burns every 1k miles it runs. S2ks are great cars don't get me wrong but they are a bit heavy compared to the competition and they make power way to high in the rev range for a car that is daily driven on a regular basis. For a track car i'd buy an s2k in a heartbeat. For a daily driver i'll take a mx-5 rf so when the top isn't down I can keep the elements off of me and don't get the soft top buffeting like all the other soft top cars I've owned in the past and also when I take it easy commuting I get close to around 40mpg(38mpg was my highest and that was cruising down the highway at around 80mph).

    • @soundseeker63
      @soundseeker63 4 года назад +4

      Couldn't be bothered to work out the BMEP, but 76.5 lb/ft per liter puts it at somewhere between the Lexus LFA (73.7 lb/ft) and the Ferrari 812 (81.5 lb/ft). Not bad for an engine that was designed over 20 years ago!

    • @agt155
      @agt155 4 года назад

      @@soundseeker63 The Jag XK6 engine from the 1940's had over 70 lb/ft per litre.

  • @armanpena3870
    @armanpena3870 4 года назад +7

    Well done! I learned a lot! Now please explain diesel engine NVH apart from high pressure inside the combustion chamber. How some diesel engines are quieter than others.... AND high BHEP on low displacment engine does it have reliablity issues in the long run with that too much stress?

    • @einstein1984
      @einstein1984 4 года назад +1

      it's the rate at which pressure increases in the diesel that's the noisemaker, some alleviate that with 1 or 2 pre injections. Also a plastic sump to dampen noise coming out the bottom helps

    • @silentIm
      @silentIm 4 года назад

      Turbocharger converts part of the noise into the turbine rotation, which used to pressurize air intake (ofcourse, exhaust pressure and heat are converted too). Modern common rail injector squirts preinjection before main injection events to dampen vibration by harmonics. Also some engines actually have intake throttle, like my Chevy Captiva. While it mainly functions to maximize exhaust gas recirculation (EGR) system, it has side effect of noise reduction. Also modern heat resistant foam that is used under the engine cover and the engine hood also absorbs noise. Balance shaft is used as well to reduce vibration and therefore noise.

  • @waxeyone
    @waxeyone 3 года назад

    Although I start to glaze over with that mathy stuff, your point was well made. It solidifies my current state of auto buying, "if doesn't have forced induction, I'm not buying it", more torque at lower RPM makes driving on the street more fun...

  • @AZ4N4774
    @AZ4N4774 4 года назад +2

    I was wondering if one common thing between the engines with high BMEP would be having large bore and short stroke. I imagine that a piston in a shorter stroke cylinder will have a higher average pressure since it travels less when compared with a longer stroke engine. Thanks for the great material, as always entertaining and interesting.

    • @KF1
      @KF1 4 года назад +2

      So a lower bmep over a longer stroke could really whiteboard the issue? Needs more math!

    • @gigagdragoon2345
      @gigagdragoon2345 4 года назад +2

      What helps is that larger bore = more valve area. Which means more potential for airflow then torque. But high valve area to cylinder wall area = lower thermal efficiency.

  • @ninjadriver0078
    @ninjadriver0078 4 года назад +5

    Wow, my 2003 V6 Mustang came out with 10.1. Although who knows maybe that isn't too bad for the time. Also Go Wolfpack!

    • @moritzm2143
      @moritzm2143 4 года назад +1

      Well my 1999 e36 323i makes 12.5🙈
      Don't get me wrong I also like Mustangs :)

    • @einstein1984
      @einstein1984 4 года назад +1

      it's terrible, murican engines always sucked at volumetric efficiency

    • @hallkbrdz
      @hallkbrdz 4 года назад +1

      @@einstein1984 Pretty much. But they excelled in sheer volume!

    • @ghoulbuster1
      @ghoulbuster1 4 года назад

      That's because you got the V6!

  • @nicolasboivin9746
    @nicolasboivin9746 4 года назад +3

    Did the test for my 2014 Aprilia Tuono and it scores...
    13.97! Higher than a Ferrari!

    • @nik7bkh965
      @nik7bkh965 4 года назад

      My Mercedes has nearly 20 so way better than you ;)

  • @forestschultz5740
    @forestschultz5740 4 года назад +12

    10:55 So you're saying some naturally aspirated engine make boost?

    • @sw1sha442
      @sw1sha442 4 года назад +5

      Yes, a cylinder can fill more than "100%" if the air charge has momentum or a higher than atmospheric pressure wave forcing the charge in. This is why intake and exhaust runners are tuned.

  • @TheNewNoise7
    @TheNewNoise7 4 года назад

    This was seriously one the most fascinating videos you’ve done to date. Freakin’ awesome.

  • @mathteacher1729
    @mathteacher1729 4 года назад

    Dear Jason (and/or his viewers),
    **Question** How is it possible for a naturally aspirated engine to exceed atmospheric pressure?
    Context: I'm a math teacher turned data scientist who was recommended this video because it had lots of math. I showed it to a bunch of friends I grew up with who are professional and hobbyist auto mechanics, and they were curious of the answer to that question.
    Other feedback: Your mathematical derivation is wonderfully clear and very well contextualized! I especially like how you explained why it is necessary to divide by 2 at the end of eq 4 and your careful handling of torque (no pun intended) in eq 7. How long did it take you to prepare the notes for this?
    I hope you and your family (and all of your viewers) are staying safe and healthy!
    Sincerely,
    Joe

  • @TotalAnomy
    @TotalAnomy 4 года назад +3

    Yeah, I've been noticing for years now that when it comes to motorcycles, despite wild variations of HP/litre between different models; there isn't that much variation in terms of torque/litre, with most of them being somewhere around 9-11 kgf.m/litre (keep in mind that virtually all bikes are naturally aspirated, AFAIK the only factory non-naturally aspirated motorcycle nowadays is the supercharged Kawasaki H2/H2R).
    Jason, have you ever thought of comparing engines in the form of some integration of the power curve? Of course this would require some consideration; for instance if it were integrated in terms of rpm, you would probably have to choose an arbitrary range of rpm (say the top 3000rpm with greatest power), and this would not be ideal if you were to compare between engines with significant variations of the rev limit... So I
    guess it could be in terms of a certain proportion of the rev range, for instance the top 50% of the rev limit (for a 6000rpm redline, this would mean the range of 3000 rpm with greatest power). I believe something like this would give you a more significant value to compare the ability to accelerate than simply peak power.

    • @jaydunbar7538
      @jaydunbar7538 4 года назад

      "Non-aspirated"? Never heard it called that before, doesn't really make sense to me either. Naturally aspirated or forced, the engine is supplied with air so would therefore be aspirated.

    • @patrollingthemojavemakesyo5948
      @patrollingthemojavemakesyo5948 4 года назад

      Still playing kill zone?

  • @AntneeUK
    @AntneeUK 4 года назад +4

    "Spreadsheets Heck Yeah!"
    Made me laugh 😂

  • @danielteivelis
    @danielteivelis 4 года назад +6

    P.S.: RR "low" BMEP for a turbo-powered engine means it is built to last (quite the opposite regardng the Ferrari engine). Also, increasing BMEP while maintaining the same engine original components (pistons, rods, cranckshafts) will ALWAYS result in shorter engine life simply because the original materials were not designed/manufactured to stand the additional stress.

    • @MeakerSE
      @MeakerSE 4 года назад +1

      This is the cost aspect of what he was saying, you are going to have to start moving to exotic materials and finer tolerances to get there.

  • @blakestone75
    @blakestone75 4 года назад +2

    I will definitely use that spreadsheet for when I design my engines...

  • @grod4844
    @grod4844 3 года назад

    wow that chart is actually very cool for seeing what upgrades might do - awesome video

  • @rishi_sk
    @rishi_sk 4 года назад +23

    As a mechanical engineer, this is Porn🤤

    • @Jimmiegame
      @Jimmiegame 4 года назад

      Switched my major right from M.E. right before thermodynamics class... however this is still porn 💀💀💀🔥🔥🔥

  • @cesteres
    @cesteres 4 года назад +19

    I don't think rolls is embarrassed about their engines...

    • @CompTechs
      @CompTechs 4 года назад

      Maybe they should be, but perhaps rich folk are impressed by throwing displacement or boost at engines instead of good engineering. As long as they sell big comfy cars I guess.

    • @muumuumu
      @muumuumu 4 года назад

      @@CompTechs for the rich folks,, bigger=better, more expensive etc..

    • @BigUriel
      @BigUriel 4 года назад +3

      @@CompTechs There's plenty of great engineering in that engine.
      You can make an engine with massive BMEP by simply lowering the hell out of compression ratio, fitting a massive turbo and intercooler and cranking up the boost until just before it blows up. Doesn't make it a particularly impressive feat of engineering.
      When the metric you're using to measure the quality of an engine gives you results that say an MX-5 is as good as an LFA that's a pretty big giveaway that that metric by itself isn't particularly useful or relevant.

    • @nik7bkh965
      @nik7bkh965 4 года назад +1

      @@CompTechs damn, people like you know nothing about cars... Rolls royce couldn't care less about a performance Stat such as BMEP, since their cars have a completely different purpose.
      The engine needs to be silent, robust and definetely not high performing (good acceleration is not important in such car). The rolls royce is perfect in that case so stop mixing up stuff you know nothing about.
      It's like saying "F1 cars are slow because they have low torque". You guys Completely missed the point.

  • @tobiasstaermose
    @tobiasstaermose 4 года назад +3

    Somehow feel like this needs a mentioning of a Honda K20 somewhere ;)

    • @thatcopenguy
      @thatcopenguy 3 года назад

      K20 makes about 100Nm/ liter if I'm not mistaken, with the Mugen FD2 Type-R being the most impressive at 110Nm/ liter and it maintained that number until peak power.
      The BMEP thing just translates to Nm/liter, and the maximum potential for N/A motors is about 120Nm/ liter and 105-110Nm/ liter at peak power.

  • @jaredbaldwin5203
    @jaredbaldwin5203 4 года назад +1

    this man actually found a good use for a box and whisker plot, what a legend

  • @GrotrianSeiler
    @GrotrianSeiler 4 года назад

    Respect to you Jason, you take the craziest concepts and explain them really well. I think maybe it’s a gift. I had a philosophy professor in college who had the same gift. Others could talk The Who semester and it made no sense. Not here. This video was SO interesting. I hope you consider applying to other types of engines. Cool.

  • @jaydenblain3599
    @jaydenblain3599 4 года назад +3

    I found a new record for lowest BMAP. the 1996-2006 jeep wranglers (and other models) had a 4L inline 6 making 190hp and 225 ftlbs. The BMEP comes out to 9.5 lol. This is actually really surprising to me considering its one of very few gas engines that make quite a bit more torque than hp.

  • @ThePiraguista
    @ThePiraguista 4 года назад +5

    I'm sceptic about all of this, in a constructive way, its nonsense.
    how do you cancel out the RPS at step 9? the crankshaft and the wheels do not spin at the same ratio, at least you must've explained the particular case of using the 1:1 gear ratio of the gearbox.
    Then you are making another big mistake, that is to take the torque at the crankshaft, because in step 7 you cancelled out the radius, and if you assume they are the same, you are using the torque at the wheels. Otherwise you'll be taking the crank radius equal to the wheel radius.
    Cool video anyway, keep it up

    • @maxdruciak2724
      @maxdruciak2724 4 года назад

      Power is made by the engine not anything else. The rest (gearbox, clutches, axles etc) is just transmitting the power.

    • @francescosergi2663
      @francescosergi2663 4 года назад

      Hi. Torque is measured at the crankshaft. Rps does not count because is the speed of the crankshaft. Transmission does not count in this calculation.

    • @DoktorBayerischeMotorenWerke
      @DoktorBayerischeMotorenWerke Месяц назад

      Measured at the flywheel, not the wheels,

  • @danstarc
    @danstarc 4 года назад +12

    No mention of Wankel engines? Missed opportunity!

    • @bradleyland
      @bradleyland 4 года назад +5

      Problem is, no one knows the formula for the area of a Dorito. It's kind of like the English word that rhymes with orange. We're not tryna create any blackholes here.

    • @danstarc
      @danstarc 4 года назад +1

      @@bradleyland you'd have to divide by zero.

    • @seanathanq
      @seanathanq 4 года назад

      Hmmm there must be a way to figure it out, technically distance traveled would be 1 rotation right? And you can get the surface area of the face, also I'm not sure how many times it fires throughout that rotation though

    • @danbert8
      @danbert8 4 года назад

      Did the math. You gotta use the 2 stroke equation and it comes out to BMEP= 10.4 Bar for the Renesis. Lower is better right?

  • @xpkbrz
    @xpkbrz 4 года назад

    Best...by far... content on the show!
    To who can understand...altough it was laid down in a very comprehensive layout
    Praise the excellent good work.

  • @_454_
    @_454_ 15 дней назад

    by god my eyes have been lit up while watching this video, i feel enlightened. The last part where you find the potential maximum horsepower of your own engine is so cool.

  • @ProphetQT1
    @ProphetQT1 4 года назад +4

    Perhaps the greatest sports car of all time xD

    • @eknaap8800
      @eknaap8800 4 года назад

      Without telling WHICH, does make it a pointless comment... 🥴

    • @EngineeringExplained
      @EngineeringExplained  4 года назад +5

      @@eknaap8800 He's referencing the comment in the video. MX-5, obv!

    • @787brx8
      @787brx8 4 года назад

      That would be the one vehicle that I haven't designed yet. It would incorporate my anti-knock engine technology, among other things.

  • @dronepilot260rc
    @dronepilot260rc 4 года назад +6

    So, basically I need a bigger turbo and bigger exhaust pipe on my Volvo T6 engine 😊

  • @RedfishCarolina
    @RedfishCarolina 4 года назад +5

    Lactose intolerance causes a lot of mean effective pressure.

    • @Shadowband72
      @Shadowband72 4 года назад +2

      You meen Gross effective pressure ?

  • @MrSpartanPaul
    @MrSpartanPaul 2 года назад

    Thanks for making videos. 👍Nobody else gets into the nitty gritty of gear head stuff like you do!!! Excellent work too, btw.

  • @ashutoshverma2828
    @ashutoshverma2828 3 года назад +2

    6:40- They'll walk away from you
    9:35- It breaks the scale, that I made up 😂😂 😂😂 Jason funny AF

  • @user-md4di6yg2p
    @user-md4di6yg2p 4 года назад +11

    "I was told there would be no math!"

  • @adventure_arsenal
    @adventure_arsenal 4 года назад +4

    It breaks the scale . ...That I made up 😂

  • @rucarnuts13
    @rucarnuts13 4 года назад +4

    Question. How could one apply this to Wankel rotary engines?

    • @codeman99-dev
      @codeman99-dev 4 года назад +1

      You'd multiply by a ratio. I don't remember the exacts of the wankel design. Is it three burns per revolution and two engine revolution equals one crankshaft revolution?
      Basically, get a ratio that removes the differences in power delivery.

  • @Bizz3642
    @Bizz3642 4 года назад

    Great stuff, In the early 80s I began to wonder why porsche and jaguar engines of less than 3.5 litres were putting out more power than 5+ litre V8 engines. It was then that I learned of volumetric efficiency. Great explanation - will do calcs for my daily driver.

  • @linusfondin464
    @linusfondin464 4 года назад +1

    I might have done something wrong, but according to my calculations a Lotus Elise cup 250 (my dream car) has a BMEP of 17,5. It has naturally aspirated engine.

    • @linusfondin464
      @linusfondin464 4 года назад

      Pi•4(250Nm)/1,798L•100=17,4727066384
      Or what I did on my phones calculator:
      Pi•4(250Nm)/1,798L = 1 747,270663843
      1 747,270663843/100 =17, 47....Bar

  • @richardbowles7690
    @richardbowles7690 4 года назад +4

    Nicely done -- and long overdue. Too much focus on horsepower and too little awareness of torque (and BMEP) as what most matters. Touche.

    • @vladulescuadrian6080
      @vladulescuadrian6080 4 года назад

      Is clear that you have no idea what you are taking about. Torque and power are in a direct relationship, so simplistically speaking they tell us the same thing. What really matters and people are not aware is that all manufactures specify only peak power/torque and what is actually important is power/torque curve over the nominal RPM range of the engine.

    • @richardbowles7690
      @richardbowles7690 4 года назад +1

      Torque is what people feel when leaving stop sign. And, people feel that many times when they drive. Peak horsepower (or peak torque) is rarely felt, if ever, in normal use. Let's keep the comments respectful.