🛠 A Perfect Power Curve - is there such a thing? | TECHNICALLY SPEAKING
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- เผยแพร่เมื่อ 2 มิ.ย. 2024
- Comparing Dyno Charts is a popular pastime within the modifying community, but what are you actually comparing? Is it just the spike at the end of your RPM showing the Max Power figure or the shape and position of the entire Power Curve? In this video, we compare power curves from a naturally aspirated 4, turbo 4, turbo 6, and a naturally aspirated V8. We also explain the differences between them and how they affect the vehicle's performance.
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“Technically Speaking” is awesome and Scott is an absolute legend 🙌
Great information! So many people just don't get peak numbers vs area under the curve. My Miata makes 313kw peak, which is cool and all, but the best part is that it makes above 400nm from 3600-7100RPM. And that's the part that makes it fun, and a great street car.
That’s cool, but i have 620nm at 1500rpm and goes to down to 550nm at 4500rpm but hp keep is basically at 270-300hp throughout the rev range
@@Xfacehack Sounds like a 335d with the stock turbos cranked up to the clouds 😂 btw 550nm @ 4500rpm = 347hp
Damn, Scott. I remember when you just started this bit, you looked like a deer reciting a poem while caught in a pair of high beams, but now look at you! TV presenting skills man, they are growing.
Small suggestion, but instead of having the 2 turbo engines with huge turbos, maybe have 2 of the same engine (eg 2x SR20 or 2x rb26) - one with a large turbo like you talked about in the video, and one with a more modest turbo. The examples used in the video make turbos seem like a terrible street option 😂
Either way, keep up the good work, love your content!
I was thinking along the same lines, same basic engine - N/A, constant displacement/Sprintex supercharger, mild turbo'd, and high power turbo'. Same engine, very different ways of producing power.
It would be really interesting to add rotary engines to that comparison. Normally aspirated 2, 3, 4 rotors and show some from turbo 2 and 3 rotors. 😎
Good point. Rotaries are a completely different animal:)
As suggested before; it would be nice to see the 'same' engine in different states of tune.
OEM atmo
Race atmo
Usable street turbo
Numbers-bragging turbo
Based on the sunburn and cast, it looks like Scotty had a dirt bike incident! Heal well Scott.
I thought that I was the only one that noticed this until I saw your comment.
Poor guy so tall he's up near the sun
and this is why the NA 4 cylinder is in practically every people mover out there!
Great info, it covered a whole lot of info that is needed to understand power specially for people getting into tuning
Really great video Scott. I going to share this with the people at HP Academy, but they probably heave already know about your vids.
BSFC is what I'm learning about right now, and the efficiency and power curves fit right in.
I came from this site to leave a like. That's how clear and interesting I found this video. Thank you very much sir.
awesome videos as always. I think seeing a small frame turbo that runs out of puff up top on that comparison would have been an interesting contrast.
Nice episode. Nothing I didn't know, but I still like hearing you say it :D Hope your hand is going to be OK soon!
Stitches coming out next week:)
I really love these kinda videos as it goes in to much more detail as to why and how a v8 makes what is does vs a k24 ❤❤
Wow thank you. This is even better than engineering explained.
could you bring up like, smal turbo vs big turbo vs compressor? That would be awsome.
Thank you! Really interesting and well compared 😃
Very good 101 on the importance of tailoring the torque/power curve of the engine build for the application it would be used for - and I particularly liked the addressing of the gearbox gearing.
Many years ago, a friend built his car with a 'race' camshaft which had a rather narrow 'power band', but couldn't afford the rather expensive close ratio gearbox it needed. In practice, it was pretty quick, for the day, in the first three gears as the engine still produced sufficient torque to pull the next gear, but it didn't have torque when going into 4th to overcome the drag forces as it was to far down the curve - the car would actually slow down. If he was on a down-hill, gravity gave enough assistance, though, and as long as he kept the speed up, and the engine in it's power band, he could use 4th effectively.
Great explanation 👌
Nice and tight presentation, very useful
EXCELLENT video.
4 vs 6 vs 8. Why do the Power Curves from these engines look so different?
Comparing Dyno Charts is a popular pastime within the modifying community, but what are you actually comparing? Is it just the spike at the end of your RPM showing the Max Power figure or the shape and position of the entire Power Curve? In this video, we compare power curves from a naturally aspirated 4, turbo 4, turbo 6, and a naturally aspirated V8. We also explain the differences between them and how they affect the vehicle's performance.
Submit your dyno graphs here: www.haltech.com/how-to-read-power-curves/
I'll take big block turbo V8, thanks.
afr related ignition timing and acceleration enrichment with or without boost
Yep love my VT ecotec on B roads as you can throw it around as holds the power curve great between 60km to 170km 👌🏻 switch back twisty 1s fantastic if don't get busted 🚔😂
I was disappointed with this video, it was super basic for the engine noob basically. Would you ever do a video talking about what it takes to make a almost flat torque curve? You could use an na LS v8 no vvt and maybe with vvt, and a turbo also. The turbo could have ecu controlled wastegate and run more boost in certain parts of the curve than others, though the response time to boost changes would be a factor. I am also curious on a typical stock ls cam with low lift vs an aftermarket solid roller cam with quicker ramp, more lift, and same duration. Love the channel guys.
I've tried explaining this too many times to my friends, the curve is way more important than the final number.
not necessery if diffrenc in peak power is really huge like in this 6 cyl turbo engine in hees egzample which make 550 kw vs this v8 which make like how much was tehre something around 225 kw let say so half of this ok there is 250 kw around if you put both grapgh on each other v8 will be stronger down lowe to some point of midrange rpm but after this thsi 6 tubro will fly away what this mean ? well v8 be better for somebody who ride slower and dont want rev so high howveer if somebody want pure racing emotion and he dont care about lowendpunch just peak punch level than 6turbo with weak lowend absolutely destroy this v8 and give you way more emotion while driving it and way stronger max acceleration again if geabox in both be perfect optimal setup ! .there be no contest 6 turbo eat on breakfast in race this particular v8 period but if we talking about slower rider which want stronger lowened than you are right this v8 make better job in daily riding if somebody dont want cross 3 or 4 k rpm or something like this .
@@mociczyczki You're kind of wrong here. Of course, you can't compare cars that are so different but lets imagine two bikes with one producing 40 bhp and 30 NM torque and another one producing 35 bhp and 25 NM torque. The second bike have more space under the graph and the first one peaks at 10500 RPM. Let's imagine you're street racing or circuit racing. The second bike is going to win effortlessly.
The only time the first bike is going to win is during or has the possibility to win is in a straight line drag. Peak HP doesn't mean shit because if its producing 40 bhp at like 10 K RPM and is only producing 10 at 2000 RPM and if it has a shit gearbox, it's going to be a super bad bike. You can fix this issue with a good gear box always.
@@mociczyczki with bad gearing engine from 15000 hp top fuell can lost with 1.0 50 hp engine
It can't. I am not replying to the rest of your crap because this comment itself shows how much of an idiot you are.
Let me teach you something.
Area under the graph is so much more important than the peak HP even for racing with an exception of drag racing.
Like always on all channels (here, MCM, and so on) , Scott is giving us absolutely amazing info and also looks like he just got out of a mutually agreed fist fight between well dressed gentlemen and won, which is why it's even more refreshing to watch! :)
Rumour has it he fought a pack of wild dingoes...
great video!
any plans for a video on reading compressor maps?
Im finally glad there is a video to give the big understanding of under the curve, i can refer all the friends with no real idea and others who think peak power is everything... that big giant turbo is by far not the best choice..
Great reference video. I'd love to see it also talk a bit more about that relation, together with gear ratios.
I ride motorbikes mostly and find that the discussions there often miss very important points on gearing and power. Usually people complaining about bikes like the KLR650 as "needing" 6 speeds, when the bike has a wide enough power / torque band that it can do without that extra gear.
I have mostly operated torquey vehicles and learned a ton from my experiences on the few peak-y race spec bikes, I've been on.
Mainly a built DRZ and 2 stroke race spec Yamaha YZF 250.
TBH, I find them nearly unusable in a normal setting because the engines just buck and complain when going at normal speeds. They taught me, why they have close ratio gearboxes with many gears, and that's purely to keep them in their narrow power band.
That math between torque and power is why the metric system exists. 😄 Just use kN and kW.
I would rather pound some feet, if that's alright?
It did make me laugh how Scotty spent five minutes explaining (really well!) how to convert RPM and LbFt into HP, and then spent the rest of the video using kW and Nm.
I think it's a Commonwealth thing that we're equally happy with metric and imperial (although I'll always use metric if I need to do maths).
@@phuzz00 Yeah, he used the process of dimensional analysis. Since the metric system is implicitly more descriptive in it's units, it made sense to use Metric for the rest of the video. I say this as an American that was taught Metric in school hand has issues when people tell me things in imperial units, especially while cooking and baking. My wife laughs at me all the time.
Great info
Godd stuff buddy enjoyed it,
We got a 2014 isuzu dmax TFS86TT 2.5TT Yukon UK spec,
And it tuned and its a monster, i swear it will be the first motor that will blow the TC led in the cluster lol,
here is my question, what would you suggest would be the next step of further performance, the tune on it is not dangerous (the tuner refuses to make a tune that will damage a engine and i like that attitude)
And so we know mechanical upgrades are next before it gets put on a dyno again, but dont need to make it wheelie but just want a bit more, its used for alsorts and does alot of heavy load towing and we live in wales so we do partake a little off roading lol
Hope the old can holder heals up soon buddy 👍
Discusses calculations & conversions for HP / FtLb but then has dyno graphs all in metric (kW / NM) 😂 Catering for 'Merica?
Great explanations though, well articulated and presented. A+ would watch again!
Great info Scotty, stay out of the sun 🌞⛅
Great video Scott, Ill upload my LS3 dyno sheet ;)
Where do we upload our dyno sheets?
www.haltech.com/how-to-read-power-curves/
www.haltech.com/how-to-read-power-curves/
Hey Scotty, my 2002 WRX was dyno tuned to 155KW at the wheels but it developed soon after a bad hesitation when accelerating and before turbo boots. The tuner stated my OEM ECU is the culprit so I recently purchased a Haltech platinum pro plugin ECU. It will be interesting if the hesitation is rectified when it is retuned with the new ECU.
Nice work
Thanks Scotty
Good trick is to graph drive wheel/hub torque /vs road speed in each gear. You can then see if it even worth considering a closer ratio trans by seeing how much gap (vertically) on the graph between max rpm in one gear compared to she road speed in next gear. And if you factor vehicle weight into the graph, you can bench race different cars against each other, assuming same type of dyno was used.
Nice TF. Would having a bigger/ medium single on an ls do the same as the turbo versions of the 4 n6? Or twins?? Would a cam be more beneficial??
From an NA engine you can only get about 110Nm/l or 81,5lbft/l, realistically a few less, in a high end race engine a few more. If you add boost you multiply the torque for every bar of boost. The amount of cylinders as well as the bore/stroke ratio does not really affect the acheivable torque but it does affect at what rpm you can deploy that torque. A point I would like to make regarding the "what is better for the street", one very important aspect is how well the engine is tuned when its not on wide open throttle. The numbers you see on the dyno is at WOT, but you rarely drive at WOT on the street, its more important with a quality tune at medium throttle around 1-5krpm than WOT torque numbers.
An NA 4cyl making 550Nm? yeah nah
Well picked! And sorry, I messed this one up!
Have displayed “Roller Torque” when talking about the dyno sheets, which is calculated against roller speed and is determinate on the size of the dyno rollers (ours are 273mm). I should have displayed “Motive Force” on our Mainline Dyno which would have made more sense. I didn’t use “Derived Torque” because the tacho was not calibrates in the Dyno software for each of the random example cars I picked.
A good read on Dyno Torque / Motive Force / Tractive Effort can be found at: www.mainlinedyno.com.au/images/downloads/DYNO_TORQUE_FIGURES_-_THE_TRUTH.pdf
PS. I seriously want a K series with 550nm of “Derived Torque” haha
Scott
@@haltech that document is a good read!
Yes...I have studied manufacturer torque claims for decades and all NA engines always make around 100Nm per liter at the crank..
Yeh I was scratching my head too lol.
I love haltech
Love it.
Thx Scotty
You need a more in depth version like V8s superchargers turbo chargers wankel engines all of them with different variations and how it effects the power bands now that would be amazing!
Be interested to see a dyno graph for older vs newer engines. IE a 2JZ vs a B58 in standard trim. Or maybe a 500hp 2JZ Vs an S58
Hey haltech, I hope you see this comment
Is the dyno consider error, if the graph of HP intersect with torque line below rpm of 5252? would that mean the dyno read heavier?
It leaves me with a question: Does it make sense to have a turbo setup ideal for circuit instead of peak numbers? I have an old bimmer 4 pots and I want to make it faster around the track, should I go for mechanical upgrades (ported head, better intake, larger valves and optimal camshaft), turbo on the mid range, or a big 5.0 SOHC V8?
as long as you get the same power numbers it no matter what type of setup engine you have but you must also take into consideration weight etc small 2,5 litre turbo with let say 500 bhp from 5000 to 7500 rpm vs 5 litre v8 with 500 bhp from 7000 to 10500 rpm give egzacly the same results on track but you must also conisder turbo lag and engine weight .
Differentual gearing and tyre size along with a tough transmission / Gearbox can change the curve very effectivly and put the power where you are most likely to use it.
You can have the most expensive and hottest motor avaliable but it won't matter if the rest is not set up correctly and don't forget you have to stop as well. Bigger power calls for bigger brakes
i have actually a question about comparisons. Vor exampel. On which engine does a supercharger or turbocharger suits the best.
"Kant BEET Kewbz"
Hahaha. Needs to be a shirt
I found this video informative. However like someone else commented, why isn't there a turbo 4 cylinder with a small turbo? What about, (and i know there is some controversy of this), a higher compression small turbo 4 chart on here?
What mods does the k24 have? And what k24 is it?
It's hard to believe that it has so much Nm.
I have just turboed my k24z3 with 5 psi. I have 252nm and 167wkw. At 7288rpm.
Im happy with the way the car drives. But i might up the boost to 9psi just to get the most of my setup and money.
Who would be a good tuner for my injected 355 Torana? Nothing special just had a new 4 barrel throttle put on it with larger injectors etc. I am on the South Coast but would drive to Sydney if needed?
Check out the "Dealer" section of our website www.haltech.com :)
Can you make a video. how the HP & Torque cure change when you convert a NA engine to a Turbo or supercharger.
Like the Subaru H6 from MCM
How about to use high compression in boost motor to counter low power in low rpm range...???
Hi over in glasgow scotland love the vids how do you convert kw into hp and how do you convert whp to hp on a 4x4 ive got 298whp evo cant get a accurate number in hp before i start with torque thanks.
KW at the wheels is HP at the crank.
Front wheel drives lose 10% less to the wheels too
Great video as always... but all the torque numbers in the world (and via math, hp/kw) don't mean anything until they're multiplied out through gearing! Broad engine comparisons are basically useless until you look at what transmission they're typically (or available to be) paired with. Imagine 2 fantasy engines - one makes 100 ft/lbs. of torque up to 8k, another is twice is big and makes 200 ft/lbs., but only up to 4k... geared appropriately, they'll both be just as fast. (not so coincidentally) their hp/kw will be pretty damn close.
That's why Scotty said he dyno'd all the cars in 4th gear, or as close to 1:1 as possible.
Great video, however it’s really funny to realise that this type of content isn’t understood by so many „car people“ out there....🙄
When did you switch to left hand?
Uploaded dyno sheet but no response, what's the point?
Supercharged (postive displacement type) engines combine best of na plus turbo for a great all round circuit/drag/street compromise. You just lose the final ultimate torque/power a turbo makes at similar boost. And about 15 psi -20 psi is probably a reasonable max boost you can get if you want to do a few circuit laps. Though you can cheat a bit by spraying water/meth through the charger...
Alfa Romeos Giulias have inline 4 cylinder , and they run really well
I don't run a Haltech ECU (yet) but I do have a dyno graph for my daily driver BMW 335xi.
There's quite a bit of information about the car but I'd like to post the graph for you guys to see
We'll have that article on our website's tech section soon and we'll enable comments/uploads:)
www.haltech.com/how-to-read-power-curves/
is Engine optimal speed range a factory setting and can not be changed,for example an engine with 3000 rpm to 4000 rpm optimal speed range or optimal speed range can be changed according to driving conditions and throttle input?
if you mean max acceleration than you have one fixed rpm range =peak power rpm is strongest in each engine period
Why would you start with HP and Ft/lbs and then switch to KW and NM?
That settles it, I am taking the turbo off my 917/30!
LOL - and K-swapping it??
@@haltech keep it flat... EJ20 for the win! In all seriousness love your content.
How about a 4 cyl with "too small" turbo, like they come from factory this days. The thing spools up @1500 or 2000 but don't make it on top, that would be the ultimate street car? A small light engine in a small light car that has all the power as soon you tatch the throtle
the NA 4 cyl is doing 150km/h at redline the others are doing 170-210 hardly a fair comparison. All may be at 1:1 gearbox ratio, but final drives (and tyres) are probably way different
This would have been better if the graphs were all scaled the same. Can you do that on the website copy?
Yes, the scale on each of these chart is different, we sized them down because we mainly wanted to compare the shape of the curve rather than the actual max hp.
was wondering where 5252 came from, thanks
the best engine for a daily car, van or pickup is a 4 Cylinder Turbo Diesel! 😆
not necessarily the fastest thing out there,
but think about it, a diesel as small as a 1.7L 4 cylinder can make 90kw as early as 2000rpm
and max out at around 105kw @ 4,000 revs
that sort of performance will push your car hard from a stand still to about your average cruising speed (80-130kph).
but beyond that rpm range you'll feel the power declining, opposite to what a turbo petrol feels like.
Why was I thinking and probably would've bet on it that it was tq X TIME / 5252??? Lol where did I get that from I wonder lol
I’m antsy to build a 260hp 2arfe NA with all Toyota parts bin mods and a Haltech
Why doesn't Haltech offer a plug n play kit for 1uzfe?
Our Elite series ECUs support the 1UZFE but it needs to be wired in. At this stage there's simply no demand for a PnP solution as most of these engines are not used in their factory cars.
What did you do to your hand, Mr. tuning fork?
Defiantly a motorbike crash
I have a perfect power curve, but convincing women that's what my beer gut is is hard.
Also this video is an excellent way to demonstrate that maths is important not just in the more esoteric science fields.
Which uses the least fuel @ 100km/h? Less power means better economy?
Not exactly, comes down to efficiency more than power.
Of these most likely the NA 4cyl is the most economic engine. Generally less power means better economy unless you're comparing with a really old engine. I'll try to make it as simple as possible: nowdays engines all have a quite similar efficiency, and the efficiency is calculated dividing what you get (in this case power) by what you use (fuel). So, if you have two engines with the same efficiency, if one makes double the power as the other it has to use double the fuel.
@@DinoTrollerino I understand what you mean by simple as possible but you know it’s not.
Big turbo motors aren’t going to be 10:1+ cr, a 6/8 is going to have more internal friction. Both impact efficiency substantially. It goes well beyond that too, I know what you mean, but it’s probably an oversimplification of it. Your ‘simplified’ statement is correct though.
@@W0O0G yes, I know it's oversimplified, but I think it's good enough for a YT comment
Malaysia hadir☺️
Can we get a what’s to special video on the SR20DET please and thank you
It's all alloy, that's it
get inline 4 5 litres and v8 5 litres for road car both have the same power curve ...., its easy to do strong lowend and relativvely strong top end while have much biger displacement than honda 2,4 litre heh but comapre the same displacement and there be no big diffrenc if you have v8 or inline 4 with similar bore to stroke and so one ...now the perfect power curve assuming we have in regulation limited peak pwoer is..... yeeep constant peak power as wide on rpm graph as posiible this reduce shifting to minimum and no matter at which rpm you are all it takes is put throtlle at max and you have max accelerationat any speed whithout reduction gear down .
If only the was a way to not be in 4th gear at 100kph so that you can be on boost. I;ll have to check my G6Et(543 rwkw)to see if it can be done. Also, why would you say, i have to put an LS in there but then you use a Skyline. In Australia you should have used the Barra.....500rwkw cars are on boost at 3000rpm.
The LS is one of, if not the most popular V8 in the mod/racing community today so it's the obvious choice to use it as an example of a V8 power curve. As much as we love the Barra, it's not available world-wide so a lot of our viewers would not be familiar with it. We thought using an RB or a 2JZ for our straight 6 power curve example would be more widely recognised.
@@haltech Fair enough but it is an Australian channel with im sure a shit load of guys with Barras that would prefer to see the LS compared to a Barra, not engines that are not nearly as common as the Turbo 6 that has been in XRs,F6s and G6Ets for 18 yrs here.
Work on the basis that there are two types of cars.
I.E. The race car and the one used to tow the race car.
Other than that cars have no use and take up space for spare parts for the racer ☺
I'm surprised the honda k24 is actually torquey. Some honda engines are known to have really low torque but a great top end. No wonder they're a very common swap in the honda community.
1:20 not true, its function of stroke/displacement.. there is i thing v12 1.6 litre peugeot rally car
I would appreciate if the scales of all plots were the same. Gives a better reference
Yes, we did discuss it before the shoot and came to the conclusion that since we are comparing the curve shapes rather than the power outputs it would be more constructive to adjust the scales and make them more comparable.
V8s are great for towing other LS’s to the rubbish tip. Barra the world
Love the mighty barra. I own a 5.0 coyote v8. Thats a different animal altogether. 8000rpm redline and she loves being up there.
@@2loco nice
Scott, I'm sorry that you sprained your wrist from writing too fast on that whiteboard.
LOL - that's what happens when you do Xtreme Math!!!
@@haltech Hi Scott, I faced with problem on my EVO, it's stuttering when accelerating and I see detonation in same time, I was watching the video about Marty's EVO 9 and I think maybe the issue it because of MD327107 crank position sensor? What symptoms it has? The service man is impotent, can't find the problem. Can be it because of that sensor?
I have a ford 5.4 and its got nothing down low 😔
Scotty, what happened to the hand?
When the Tuning Fork meets a Tuning Knife, things can happen...
I once raced my 1.8 litre, 8 valve diesel Mondeo (with 125ps) against my mate's Focus 2.5 i5t (with well over 500ps). The rule was: "3000rpm limit". Guess who won?
you ? 🤔
@@mociczyczki you guessed it.
I get all the peak versus usable power talk and its explained well in this video. However. Your not gonna have your big turbo 4 or 6 in 4th doing 60 and put your foot down. Your gonna slap that shit back into 2nd or 3rd and get the rpm up so your closer to your usable power. But yeah no hate I get what the video is explaining.
how the hell is the 6.2 LS making 840 nm? General rule of thumb is that an engine will not make that much over 100 nm of torque per liter at any rpm. Some really high revving engines can get a bit above 100, but not much more
135,48 nm per liter is big number for n/a bmw s1000rr have 113,13 nm/liter and ktm superduke 1290 have 107,6 nm /liter .me cb 500 stcck clock 94,18nm/liter now after some light tune it clock 102 nm/liter with much better lowend than stock however peak performence for race are egzaacly like in stock setup .
And then along comes an engine with a Lysholm twin screw on it :D
How about a factory barra, wheels best engine of all time produced by Straya
Best under 300kw, then your head studs pull out (never heard of another engine doing this) and rods bend.
Thats why we have gears
What about diesel?
Guy just explained why there is no replacement for displacement with basic math 😂
Somebody has been in the sun 😂
I believe a 4 cylinder would make more torque than a V8 if the capacities were the same. With motorbikes a 600cc single piston will make a lot more torque than a 4 cylinder V twin.
That's what Donnan said 15 years back. He pointed at some huge Porsche 2.4l 4cyl
i dont have fulll knowledge about this but i think no and both cylinder qquantity and setup can make similar torque number = it all reallly comes to one factor .... bore to stroke ratio this is hollly grall of engine characteirstic and in me opinion most importnat factor which made engine characteristic in thsi way and not in that way offcors asusming the same displacement and both n/a or both with some charge but maybe you are right i just dont have full knwoledge and maybe some factor havve impact on this :x but which ?
840 Nm from a naturally aspirated 6.2 liter? That seems a bit optimistic, that equates to more than 135 Nm/liter!