In depth thought about supercharger vs turbocharger workings

>>13999400
Both the turbo and supercharger basically replicate a higher displacement engine. If you have a 2.0L engine and are boosting it to 2atm (14.7psi I believe) you are essentially displacing 4.0L worth of air, hence you can use enough fuel to burn with that 4L of air.

I will get to economy next.

>>13999400
>Does turbos JUST increase the RPM gain at higher RPM

the fuck?

>or does the exhaust turbine forces more compressed air into the cylinder

no shit it does this its a compressor

>making the computer give more fuel

computer is irrelevant

>decrease efficiency as long as the Turbo is working?

no

turbo engines can get over 100% effeciency
Na cannot

>wouldn't it mean that they dont reduce efficiency at all,

no

supercharges use horsepower to make horsepower and are less efficient than turbos

>>13999434
>computer is irrelevant
Except its not. Turbos only work thanks to the computer allowing more fuel as air intake increases

Here's what I know
It takes 70hp +/- to run the supercharger on the SRT Hellcat.
Superchargers sound better.

>>13999433
So this proves Turbos decrease efficiency, but does superchargers force more air directly into the intakes? or do they just pressurize it at high temps?

>>13999446
you dont even have basic turbo knowledge lel

people have ran turbos long before computers were a thing on cars

>>13999400
>>13999433
From what /o/ has taught me on turbochargers and efficiency:

When a small engine is being used for city driving at lower RPM's, the turbo isn't spooling up much. So the boost isn't very high and your 2.0L engine might only be running with the power and efficiency of 2.5L of displacement.

But when you punch the throttle end get up into the revs, that's when the turbo spools and your 2.0L engine can start burning 3.0L and 4.0L worth of air/fuel.

So a 2.0L turbo engine will get worse fuel efficiency than a 2.0L N/A engine. Close to it with city driving at low revs. But when you punch it, it has the potential to make the power of a larger engine by compressing more air and fuel.

Engines with those power adding tools are not proper engines.

Engines don't need that stuff. If anything is not right

>>13999461
But then they would be useless, the increased intake of air wont mean shit if the car cant handle it with increased fuel input, and the car will never know when to increase the fuel input between turbo running or not without a computer.

>>13999473
>what is a carburator

>>13999465
That's not the point of the thread. I dont hate that opinion, i am a fan of flat torque curves, but some people just want more power without having to rebuild their entire engine, or do it AND add a turbo/super just to add more power

>>13999479
Carbs can only adjust to the RPM levels, AFAIK they do not adjust to the fuel/air mix. I could be wrong but that's why unless your carb is modified real time by an ECU the turbo will not do shit. Same if you stick a turbo and do not modify the fuel/air program

>>13999473
>>13999494
yes

Im sure you know more than the people who engineered turbos and installed them back in the day

I guess every carbed turbo setup is a lie too

op confirmed grade a retarded

>>13999450
Turbos and superchargers do basically the same thing via different means. Not all superchagers have the fuel injected before the charger. And superchargers can be intercooled and turbos sometimes aren't intercooled (especially at low boost).

And turbos aren't inherently more efficient. But they create the potential for power out of a smaller engine. The plus side is that most of this power comes at higher RPM's. So the small engine will act like a small engine and sip fuel when the driver keeps the RPMs low. But it still has the ability to make plenty of power when the driver wants it.

So the 90% of the time the driver doesn't need 250HP, the engine will sip fuel like a 140HP engine. But when the driver stomps on the gas pedal and hits 4000RPM+, the power is there and it will drink more fuel than a similar engine without a turbo.

So basically small displacement engine most of the time that sips fuel with the ability to burn fuel and make power like a larger engine, but only when really needed.

>>13999499
Except i am not calling bullshit on them? i am just trying to ask for someone to help me understand the technical aspects of the function of a turbo related to their mix

>>13999513
youre saying they dont do shit

thats calling bullshit bruh

a turbo is going to make more air for the engine and more air = more power

it doesnt need a ecu for that

>>13999494
>>13999499
That's an interesting point. I'm guessing they are probably running real rich at low RPMs (thus negating any economy of a turbo) or the line for fuel v RPM isn't linear and as the RPMs rise in a linear fashion, the amount of fuel rises more exponentially. Like where normally at 4k rpm, you would have 4x the fuel as at 1k rpm, maybe you would be pumping 6x or 8x as much fuel with a turbocharged engine.

But I don't know shit about carbs.

>>13999532
But i thought increased air compression wouldn't do shit without the proper fuel adjustements?

>>13999541
no

the increased air is going to make the power

you need more fuel so you dont end up with so much air you run lean and accidentally your whole engine

turbo>super

>b-but muh 1 line

these are 3

>>13999554
But if air alone with the same fuel mix would be enough to increase power then why isn't this featured already used with NA engines with the carbs or fuel injections?

>itt nobody with any engineering knowledge
this shit is rich

>>13999555
Well, i guess i cant argue against double trips

I have driven and owned both supercharged and turbo cars.

Turbo is usually better for smaller displacement engines due to SC having parasitic losses on an engine

>>13999541
>But i thought increased air compression wouldn't do shit without the proper fuel adjustements?

it wont. But carburetors are totally capable of adding more fuel with more air flowing past it (that's how carbs work). esp. in a suck-through setup (carb before compressor) all the turbo would do is draw more air through the carb.

>>13999587
Yeah yeah

"MUH PARASITIC POWAH!" Its not really something i dont hear whenever i search about anything related to a supercharger, besides, since the power consumption before the gain always depends on the weight of the supercharger parts, and with modern technology they are getting lighter.

>>13999577
>>13999554
more air does not make more power.
more air does not make more power.
more air does not make more power.

More air means you can add more fuel
which means you can burn more fuel
which means you can make more power

>>13999594
Yeah, i thought that all turbos had to suck the air before the carb or injection, but since superchargers and turbochargers does very similar things regarding their workings when they suck the fuel/air mix, i want to know if even a car with a carb and an ECU is capable to modifying the fuel intake real time, in case the turbo is sucking air before the carb. I know this is done with the computer if you have an injection system, but it was never clear to me if the carbs could do the same, or if its all dependant of having an engine with ECU.

>>13999577
a turbo (and super) pumps more air than you can get NA

obviously

theres more to it than just the mixture

>>13999602
yeap

thats why just adding a turbo and changing nothing makes more power

>>13999622
Yeah, but using your logic then the mixture could still be poorer and increase power, but then it wouldn't add up to the basics of combustion and fuel/air mixtures.

>>13999609
>a car with a carb and an ECU

from my understanding, carbs operate on the venturi effect aka air flowing through a nozzle causes a low-pressure zone which draws fuel out. The more air flowing through the carb, the lower the pressure, the more fuel comes out. No computers required, m80, so sure, it's adjusting in real-time.

>>13999632
wat

if youre adding air then the mixture wont be the same

>>13999647
Yes, this is how carbs works, and it does explains a lot, it tells me that because of that, the only difference between superchargers vs turbochargers is parasite power vs lag, however, there is something else that i still cant warp my mind around, and that's the added effect of compressed air or fuel/air mix, unless i got turbo/supers all wrong and they dont compress the air but instead just force more aire through.

>>13999667
they compress the air which means more air and fuel both can go in

its called forced induction for a reason

>>13999598

It's true though, I've owned both a SC car and a TC car and although I like the instant boost and the noise of a SC I always felt the TC was faster more efficient

>>13999677
So literally the entire point of the compression is to fit more? i thought that having a compressed air-fuel mix would burn with more force than an uncompressed air-fuel mix of the same amount

Ugh so much misinformation...
There is is no reason to use a supercharger over a turbo nowadays, turbo tech has come a long way.

Carbs don't jut spray a constant volume of fuel. it changes depending on engine airflow.

All the fuel injected turbo kits back in the day just used a rising rate fuel regulator, no ecu tune.

>>13999400

Drivetrain loss and wearable vs. Lag and extra heat.

>>13999690
....


Go look up compression in a dictionary

File: 147803d1327651205-hellion-power-systems-15228-2003-ford-mustang[1].jpg (90KB, 640x480px) Image search: [Google]

90KB, 640x480px

Why not both?

>>13999667
>added effect of compressed air or fuel/air mix, unless i got turbo/supers all wrong and they dont compress the air but instead just force more aire through.

Turbochargers and superchargers both compress air. The increased density of the air is the means by which more air is "forced through".

The reason you see more turbocharged engines for fuel efficiency is that they're really efficient off boost, but then they have power on boost.

>>13999714
But wouldn't the same volume compressed by a turbo/super will also have an effect in increasing the force it will make when burning?

>>13999690
>So literally the entire point of the compression is to fit more?

well yeah

a forced induction engine is probably going to be dealing with more air and fuel but a 13:1 AFR is a 13:1 AFR

in regards to efficiency...
adding power to a car usually increases efficiency
(if tuned properly)
(if you keep your foot out of it)
(if the air compressor is in its efficiency range)
(if air fuel ratio)
(if ect...)

>>13999733
>But wouldn't the same volume compressed by a turbo/super will also have an effect in increasing the force it will make when burning?

I'm going to go with "probably not that much" but higher compression ratios also make more power so i can't give a straight answer.

we're talking about a chemical reaction here, there's a given amount of energy in a given amount of fuel being burned

What sort of power would say, a 100hp engine make if you strapped a supercharger that needs 100hp to spin to it? Or would it not work because the engine doesn't make 100hp at idle? If not, what if you had a 100hp at idle engine and strapped a supercharger requiring 100hp to spin to it?

>>13999711
most engines cant handle that kind of CFM
most HP/TQ goals dont require both
2 kinds of systems complicate routing of oil lines, ect...

turbo and super work different ways at different rpm ranges. thats why some cars use both

>>13999765
>What sort of power would say, a 100hp engine make if you strapped a supercharger that needs 100hp to spin to it?

is it a roush?

>>13999763
The reason why i have to make that question is because turbos/supers BOTH compress more air and fuel to fit more of it, AND increase the compression ratio, even without adding more air/fuel of the NA version of the same engine, then turbos/supers would be having a bigger power output by both compressing the air and fuel instead of just the air alone, at the expense of increased risk of breaking the entire engine. Of course, maybe this could be different with diesels, since highly compressing a diesel/air mix before it reaches the cylinder could mean an early combustion and either break the engine, the turbo, or fuck up several intake parts, or all of the above.

What in the epic fuck is going on in this thread? If it's this confusing to you people go look up the old turbo mustangs forum and read the turbo bible. You simple fucks.

>>13999765
Well, since both supers and turbos are based on the RPM rather than NA engine power, i think your question would rather be "how much power would i earn if i added a turbo that spins at a few RPM lower than my redline"

>>13999434
>turbo engines can get over 100% effeciency
>Na cannot
You're confusing volumetric efficiency with thermodynamic efficiency. Turbo engines typically have higher BSFC than their naturally aspirated counterparts, despite performing better on steady-state fuel economy tests.

File: 12000dollarturbo.jpg (83KB, 1024x768px) Image search: [Google]

83KB, 1024x768px

>>13999814
turbos are based more on load

You can be spinning at 8000rpm and making no boost, or 2500rpm and making full boost, depending on engine load

>>13999801
> turbos/supers BOTH compress more air and fuel to fit more of it, AND increase the compression ratio
Turbos/Supers DO NOT increase compression ratio. go google compression ratio

>compressing the air and fuel instead of just the air alone
air compresses, fuel doesn't, because fuel is a liquid,and liquids are essentially incompressible. Diesels work because the air heats up so much due to compression that the fuel ignites.

>>13999813
this

>>13999433
does a turbo save any weight or bulk compared to just putting in a larger engine ?

http://www.ultimatecarpage.com/spec/698/Renault-RS-01.html
this thing has a little more power and weight than most
but that is with an iron block and very crude turbo and efi

>>13999878
>does a turbo save any weight

It can, depending on what engine you were thinking about swapping in. Or it might add weight, if you're turbo'ing an iron block instead of swapping in an ally block

Too many variables

>>13999849
>air compresses, fuel doesn't, because fuel is a liquid,and liquids are essentially incompressible
Yeah.... but i was implying a situation where a turbo/super was compressing fuel AFTER it became gaseous due to the carb/injection system.

>>13999846
I get what you mean, but its not so related to base engine power as much as the exhaust the car produces, wich is mostly related to RPM. Of course, having a higher base power engine with a turbo will create more power at the end than a smaller engine with the same system, but its not like being above X BHP all turbos magically work. In fact, i think you could modify the exhaust before it reaches the turbo to increase the load without changing the base BHP nor the RPM the engine provides.

>>13999918
at no point is the fuel a gas.
>what is atomization

>>13999939
Allright, fuel gas spray due to atomization, if you really need that term. Wouldn't the atomized fuel/air mix after going through a turbo (the mix, not just the air) be more compressed when entering the cylinder?

>>13999494
Are you fucking retarded? How would a carb know what RPM the engine is running at? Do you have any knowledge at all? If a carb only operated based on engine RPM, how would part throttle work? Idle?

>>13999988
It seems you misunderstood me. I didn't mean that the carb knew at what RPM the engine was running at, i thought that the carb would have a set fuel ratio regardless of the air entering the engine. (then i was proven wrong and that the carb adjusted the fuel based on the air intake)

>>13999494
https://www.youtube.com/watch?v=wyspAHrMbb8
shits arcane

>>13999801
You would just have to use a higher octane fuel or variable valve timing to prevent detonation, but I don't think that a turbo or super really increases the compression ratio, I don't think they provide more pressure that the cylinders already do.

>>13999960
Pressure isn't additive you simpleton

>>14000054
So that being the case, i take for granted that a turbo that compresses the mix and one that compresses only the air alone will create the same amount of power, but the one that only compresses the air will have a lower chance of premature detonation, and that being said, literally the only difference between a turbo and a supercharger assuming they provide the same air compression is the lag vs parasite power. Is that correct?

>>14000110
It would depend on the specific vehicles architecture but identical engines, one with turbo one with super, yes.

>>14000110
Except the premature ejaculating the fuel air mix, that pressure won't be even close to detonation , even more so for diesel.

NRFD

>>14000141
>>14000161
Thanks, when i made the thread i thought that superchargers would compress the air and turbos would force more air into the engine, now i know that they both compress and force air into the engine though different means.

Its all about the snail

>>14000009
My bad m8, it's been a long day. However, judging from your responses in this thread, you have a severe lack of understanding in regard to how engines work. I ain't trying to talk shit, but that's the truth. Some of your questions can't be answered because they make no sense. I'll go ahead and try my best to answer your questions in the OP, and where I see a lack of understanding, I'll try to clear it up.

Q1 "does turbos just increase the rpm gain..."
This doesn't really make sense as a question. I'll assume that "rpm gain" means horsepower.

The most important thing to know when talking about forced induction is pV=nRT.
Pressure * Volume = (moles) * (gas constant) * Temperature.

A mole is just an amount, it's a number. For our purposes, assume that moles is *the number* of oxygen atoms that we force into the engine. The volume is the displacement of the engine (in other words, we CAN NOT CHANGE the displacement). Pressure is the pressure of the air in the intake, and temperature is the temp of the air. The gas constant is just another static number that we don't really need to worry about.

So what does this tell us? The END GOAL of all forced induction is to increase the MOLES of air in the engine. The VOLUME of the engine can NOT change, so we increase the PRESSURE of the air to increase the MOLES of oxygen. As a side effect, the temperature of the air going into the engine increases.

So, with that in mind, let us describe how turbos and superchargers are different in regard to efficiency. All that an engine really does is use heat to do work. If you had a pringles can that was empty, with a tight fitting plunger, with a weight on the top, the plunger would descend into the pringles can and stop when the pressure from the air in the can on the plunger was equal to the weight on the top of the plunger. If you were to heat the air inside the pringles can, either Pressure or Volume would increase (PV=nRT). (n and r do not change in this example).

>>14000331
Yeah, i already got my questions answered. But no, i didn't meant that Turbos increased the RPM gain, i mistook it for the increased mix that goes into the cylinders, wich is what causes the extra RPM gain at high RPM.

>>14000331
In this example, the volume would increase until the pressure inside the can was equal to the weight on top of the plunger. So, we used HEAT (heating the air) to do WORK (lift the weight on the plunger). A normal car engine does the same thing, it uses heat from the combustion to do work on the piston in the cylinder.

Here's the key - the more work we do for a given amount of heat, the more efficient our engine is. It may seem abstract at first, but turbos are a way to do MORE WORK with the heat from the combustion. By spinning the exhaust turbine with the Hot Exhaust gases, you use the HEAT in the exhaust gases to do WORK.

That, in short and with a lot of hand waving, is how turbos increase the efficiency of an engine. It may not increase the mpg of the engine, because you still need a certain amount of fuel for a given amount of air, but you are using waste heat to do work.

Superchargers don't really increase the efficiency in any similar way. However, it does increase the power potential for a given engine.

There is a lot of handwaving in this response, so let me know if you have questions and I'll try to clear things up.

>>13999494
uh, the carburetor's only job IS to maintain a proper A/F mixture, whether NA or forced induction blow through or draw through

Lol at this thread.

OP (and some of you repliers) you have some fundamental misunderstandings about how an engine works and you should figure those out before trying to learn about forced induction.

>in depth
more like the 101 basics

>>14000367
RPM has nothing to do with horsepower. Absolutely nothing.

If your engine can only turn 9k rpm it doesn't matter if it makes 500 more hp than stock it's still not gonna turn more than 9k rpm.

>>13999434
>turbo engines can get over 100% effeciency
So it actually generates energy from nothing? It sounds like that's what you're saying.

>>13999434
N/A can get over 100% VE at certain rpms with tuned manifolds.

But, VE is fucking meaningless. Of course forced induction is over 100% VE.. it's compressed air.

>>14002405
volumetric efficiency and fuel efficiency are not related

>>13999691
>b-but muh bug catchers....

>>13999765
>Can you divide by 0?

>turbo
>supercharger

Doesn't matter, both are inferior to VTEC.

>>14002381
Rpm is precisely half of horsepower. Hp = force x distance force being torque and distance being how far that force travels, or Rpm.

A large displacement v8 with a long stroke will make lots of torque, but might not spin very fast when compared to a 1.6l formula atlantic 4age with a red line of 10,500 rpm

>>13999433
1atm=14.7psi

>>14002589
HP and RPM are not related, period.

What you just typed doesn't refute that in any way.

>>13999450
>So this proves Turbos decrease efficiency

Not quite. It increases power at which would be considered fuel deficient if the engine was forced to be able to produce more. But how people confuse the turbo as being more efficient is because of engines made smaller that use less fuel per cylinder size or count while maintaining power requirements. The latter however is more power per rotation by forcing fuel to burn hotter or cleaner for high emission engines.

File: being_stupid.jpg (35KB, 338x305px) Image search: [Google]

35KB, 338x305px

>>14002618
>hp and rpm are not related

>>14002589
>a large displacement v8 might not spin very fast

nascar engines can do 10k
stock age can do 6.5k

do you think the difference between them has anything to do with horsepower? No

>Rpm is precisely half of horsepower.
fucking lol. literally what. no. just no.

>>14002624
They aren't. I'm sorry that you're fucking retarded, but they aren't.

Adding more horsepower isn't going to make your engine rev higher.

>>14002630
Nascar engines use "over square" designs in which the bore diameter is a greater length than the stroke of the piston, allowing for higher speed pistons and high engine speeds, thus, more horsepower.

Also, sorry, I'm baked Rpm is half of the equation, in a sense.

>>14002635
No, but letting your engine Rev higher, by means of all necessary mods will increase horsepower

>>14002656
Most cars are over square. I'd even say like 99% of cars are oversquare.
My car is over square doesn't mean it revs to 10k.
4age is oversquare still has a 6.5k redline.

Increasing RPM yourself with lighter components and a better valve train will increase horsepower, obviously since horsepower is a function of rpm (if your engine can flow that much)

But adding horsepower isn't going to change your rpm. Which is what my first reply says, because it's replying to someone who thinks horsepower affects rpm.

>>14002660
Yeah but that has nothing to do with what I'm replying to.

And that's only if your head, intake, and exhaust can flow that much air.

>>14002685
>shitposting this early in the morning

>>14002702
It's not my fault your dumb ass can't read.

And since horsepower won't necessarily increase with rpm you're basically fucking wrong anyway.

File: image.png (171KB, 500x332px) Image search: [Google]

171KB, 500x332px

>>14002618
>HP and RPM are not related, period.

I am OP and even i know you are wrong.

>>14002712
>And since horsepower won't necessarily increase with rpm
But it will. Its ok if you thought like i did that HP torque and RPM are 3 different values, but the truth is that HP is just a number that comes from a calculus of Torque and max RPM just to please some people. If you get a stock car, increase its redline by 1k RPM and you put it on the dyno, its the most likely it will have increased HP, or not, if the engine is too shit and it cant increase overall BHP by just adding a bigger redline.

>>14002757
>or not
So you're repeating exactly what I just said. Trust me, I know more than you. I don't need you to tell me the relationship of RPM, torque and HP.

>>14002743
They aren't in the way the you think they are. Which is why I replied to your stupid as fuck post in the first place.

>>14002785
>Trust me, I know more than you
I dont trust you because you seem to know shit.

>>14002712
It's not my fault you're a cunt, but here we are.

File: come on now.jpg (48KB, 708x388px) Image search: [Google]

48KB, 708x388px

>>13999400
>In depth thought
>/o/

>>14002785
>So you're repeating exactly what I just said
I am not, i said "or not" in case the torque at high RPM of a shitty engine was so low the HP would not increase if we extended the redline. In most engines, the non shitty ones, if you DO extend the redline you WILL see an HP increase.

>>13999461
>>13999473
Carburetor tuning was their "computer" if they had a turbo on a carb. They'd simply tune it to drop more gas when the turbo was engaged

>>14003463
What are you and Idiot? do you not know anything when it comes to cars and simple mechanics. what the fuck do you mean by "Computer" adjusting the tuning wont make a diffidence if you knew anything. Go get educated kid.

>>14003471
see
https://www.youtube.com/watch?v=wyspAHrMbb8
Learn to read you donut. I said that the carb would replace the computer in terms of turbo tuning. The tuner would change the carb's setting to go along with the turbo's psi's.

>>14003508
Its the other way around, the carb cannot be tuned real time as well as an fuel injection system.

>>14003526
I see what you mean. The thing is that ECU's have made tuning a lot easier with injectors n what not. At the right hands a carb can definitely be tuned to be as good if not better than fuel injectors.But It's difficult as hell.

>>14003550
>At the right hands a carb can definitely be tuned to be as good if not better than fuel injectors
Better? yeah, i dont believe that

>>14003560
look at some people's oldschool racing set-ups they're pretty gnarly and you'd be surprised what can be done with a carburetor.

>>14003605
i have no doubt on that. I doubt that you said that a carb can surpass in any way an injector

>>13999494
>people who shit talk carbs have this knowledge level

>>13999446
>>13999494
Are you fucking stupid? What do you think a fucking vacuum reference fuel regulator is?