what is twin turbocharging or supercharging?

[cprince]

Hi! I want to know what is twin turbo charging or supercharging? Does each turbo charger or supercharger deliver to half the of the cylinders and the other one deliver to the other half of cylinders? Or is it in stages(one turbo/super charger boost the output of the other)? Thanks.

 

[Demo24]

Never heard of twin supercharging.

As for twin turbo. Can be several ways. Most common is to have as you mentioned, it split up. Ex: v8 twin turbo. one turbo for each bank of 4 cyl.

The other way is for there to be two turbos boosting the same bank of cyl. What happens is a smaller turbo takes over for the lower rpm range, once at a certain level the flow switches to a larger turbo to take it on up to redline. This helps take care of low end lag, and higher end boosting issues.

 

[Howard]

Supercharging is pressurizing the intake to increase the amount of air (which increases oxygen mass flow). This in turn allows the engine to burn more fuel, creating more power.

Turbocharging is a form of supercharging where a turbine which is powered by the exhaust gas spins a compressor. The compressor is what pressurizes the intake. Contemporary usage of the word "supercharger" is taken to mean a crank-driven supercharger, which is usually positive displacement (a specific volume moved per revolution), but can be centrifugal.

Parallel turbos handle their own cylinders, usually one of two banks or sometimes half of a inline 6. "Biturbo" is generally the same thing. Sequential turbos operate such that a smaller turbo is powered by the exhaust at low RPMs and the larger turbo kicks in at a higher RPM to reduce the boost lag.

 

[overst33r]

www.howstuffworks.com

 

[Pacfanweb]

Super or Turbo charging forcing more air into the engine than the engine could suck in by itself. You then add the appropriate amount of fuel to keep your mixture correct. And the engine has more power.

Air/Fuel mixture compressed and ignited=explosion

More Air/Fuel mixture compressed and ignited=bigger explosion

Bigger Explosion=More Power

Superchargers are belt-driven

Turbos are exhaust-driven.
That's really about the only difference....at the end of the day, they both force more air into the engine...just in different ways.

Twin superchargers or turbos simply means you have two of them forcing air into the engine.

 

[Demon-Xanth]

I've seen twin on both, superchargers are rather rare though. All twin means is that there's two. How they're arranged varies from just using two smaller ones in place of a single larger, to using one on each bank, to using two different sizes to help reduce lag. There are also compound turbo setups where one blows into the other to raise the boost levels as well as turbo+supercharging setups. Though the latter two I don't know of any that have been used on a production car.

 

[Demo24]

Originally posted by: Demon-Xanth
I've seen twin on both, superchargers are rather rare though. All twin means is that there's two. How they're arranged varies from just using two smaller ones in place of a single larger, to using one on each bank, to using two different sizes to help reduce lag. There are also compound turbo setups where one blows into the other to raise the boost levels as well as turbo+supercharging setups. Though the latter two I don't know of any that have been used on a production car.

the supercharger+turbo setup is being used by VW over in europe.

 

[Fenixgoon]

twin turbos (typically) have two setups - biturbos, where two turbos are acting in tandem and split between banks of cylinders, or sequential tubos, where one small turbo is used for low speed acceleration and a larger one for high speed acceleration (it helps prevent turbo lag). however, i don't think there's much an issue with turbo lag anymore.

 

[Toastedlightly]

Originally posted by: Fenixgoon
twin turbos (typically) have two setups - biturbos, where two turbos are acting in tandem and split between banks of cylinders, or sequential tubos, where one small turbo is used for low speed acceleration and a larger one for high speed acceleration (it helps prevent turbo lag). however, i don't think there's much an issue with turbo lag anymore.

If you aint got lag, you aint got a big enough turbo!

 

[Zenmervolt]

Originally posted by: Toastedlightly
If you aint got lag, you aint got a big enough turbo!

Lag can definitely be fun. I remember my first ride in a 944 Turbo (951); we took off hard in 1st gear and I remember my thoughts going exactly like this:

"This isn't that fast, my non-turbo could do thi--HOLY SH!T!!!"

Guess where in that train of thought the boost came on.

ZV

 

[Toastedlightly]

Originally posted by: Zenmervolt

Lag can definitely be fun. I remember my first ride in a 944 Turbo (951); we took off hard in 1st gear and I remember my thoughts going exactly like this:

"This isn't that fast, my non-turbo could do thi--HOLY SH!T!!!"

Guess where in that train of thought the boost came on.

ZV

I find it fun to break the tires loose at around 4000 rpm instead of the usual 2000. Just sorta scares the shit out of ya.

 

[Howard]

Originally posted by: Toastedlightly
<div class="FTQUOTE"><begin quote>Originally posted by: Fenixgoon
twin turbos (typically) have two setups - biturbos, where two turbos are acting in tandem and split between banks of cylinders, or sequential tubos, where one small turbo is used for low speed acceleration and a larger one for high speed acceleration (it helps prevent turbo lag). however, i don't think there's much an issue with turbo lag anymore.</end quote></div>

If you aint got lag, you aint got a big enough turbo!

VGT, baby.

 

[Fenixgoon]

<div class="FTQUOTE"><begin quote>Originally posted by: Howard
<div class="FTQUOTE"><begin quote>Originally posted by: Toastedlightly
<div class="FTQUOTE"><begin quote>Originally posted by: Fenixgoon
twin turbos (typically) have two setups - biturbos, where two turbos are acting in tandem and split between banks of cylinders, or sequential tubos, where one small turbo is used for low speed acceleration and a larger one for high speed acceleration (it helps prevent turbo lag). however, i don't think there's much an issue with turbo lag anymore.</end quote></div>

If you aint got lag, you aint got a big enough turbo!</end quote></div>
VGT, baby.</end quote></div>

vgt?

fwiw, i have a vw passat 1.8T with the stock KO3 turbo, and that's fun as hell. god help me if i ever sat in a B5 S4 or RS4 (twin sport KO3's and KO4's, respectively)

 

[Howard]

variable geometry turbo

 

[Jahee]

Originally posted by: DEMO24
<div class="FTQUOTE"><begin quote>Originally posted by: Demon-Xanth
I've seen twin on both, superchargers are rather rare though. All twin means is that there's two. How they're arranged varies from just using two smaller ones in place of a single larger, to using one on each bank, to using two different sizes to help reduce lag. There are also compound turbo setups where one blows into the other to raise the boost levels as well as turbo+supercharging setups. Though the latter two I don't know of any that have been used on a production car.</end quote></div>


the supercharger+turbo setup is being used by VW over in europe.

Golf GT?

 

[AgaBoogaBoo]

Originally posted by: Zenmervolt
<div class="FTQUOTE"><begin quote>Originally posted by: Toastedlightly
If you aint got lag, you aint got a big enough turbo!</end quote></div>

Lag can definitely be fun. I remember my first ride in a 944 Turbo (951); we took off hard in 1st gear and I remember my thoughts going exactly like this:

"This isn't that fast, my non-turbo could do thi--HOLY SH!T!!!"

Guess where in that train of thought the boost came on.

ZV

Hehe, it's so amazing initially to feel that surge of power as the turbo spools up

 

[imported_Truenofan]

<div class="FTQUOTE"><begin quote>Originally posted by: mariok2006
www.howstuffworks.com</end quote></div>

howstuffworks ftw, love that site.

the last generation of the toyota supra, had bi-turbos, one small one large, the 92-95 mazda rx7, had twin turbos(the 86-91 had only one, the name TurboII was only because it was the second turbo rx7 by mazda), two the same size, only one exhaust portion though(very interesting looking turbo imo). then there's always the single turbo. but remember this, the more air you add, the more fuel you will consume and the more heat you will generate.

edit: i just read up on a great article on one different point on turbos, superchargers, and n/a engines, as you go higher, a n/a engine will lose power, of course, air density. superchargers will have the same effect since it cannot spin any faster due to fixed gears. turbochargers on the other hand, the wastegate(a part of the turbocharger that limits how much boost you create) will stay closed longer causing the same amount of boost to occur up to a certain altitude where it can no longer create it due to outside air density.(this is a breif version of the article, still very good difference)

 

[overst33r]

Originally posted by: Truenofan
<div class="FTQUOTE"><begin quote>Originally posted by: mariok2006
www.howstuffworks.com</end quote></div>

howstuffworks ftw, love that site.

the last generation of the toyota supra, had bi-turbos, one small one large, the 92-95 mazda rx7, had twin turbos(the 86-91 had only one, the name TurboII was only because it was the second turbo rx7 by mazda), two the same size, only one exhaust portion though(very interesting looking turbo imo). then there's always the single turbo. but remember this, the more air you add, the more fuel you will consume and the more heat you will generate.

edit: i just read up on a great article on one different point on turbos, superchargers, and n/a engines, as you go higher, a n/a engine will lose power, of course, air density. superchargers will have the same effect since it cannot spin any faster due to fixed gears. turbochargers on the other hand, the wastegate(a part of the turbocharger that limits how much boost you create) will stay closed longer causing the same amount of boost to occur up to a certain altitude where it can no longer create it due to outside air density.(this is a breif version of the article, still very good difference)

The MKIV supra had equally sized sequential turbos. The FD Rx7 had two small sequential turbos.

 

[Demon-Xanth]

Just because someone's going to come by and ask (they always do):

Naturally Aspirated:
Advantages- simple, easy to tune, easy on components
Disadvantages- if you want more power, you either add displacement or RPM, both come with thier own sets of advantages/disadvantages

Supercharged:
Advantages- more power for the same engine, easier than a turbo to plumb for a non-intercooled setup, slightly easier for an intercooled setup, easy to add on aftermarket
Disadvantages- parasitic drag, not as efficient as a turbo, creates heat and takes up space in the engine bay, heats up the incoming air, takes a bit more to tune them well

Turbocharging:
Advantages- even more power for the same engine, not as affected by altitude, easy to "tune up"
Disadvantages- lag, creates a good deal of heat in the engine bay, requires a good deal of plumbing, heats the incoming air, takes heat away from the catalytic converter which causes a problem for OEM emission certification

Notes regarding the last: lag isn't as much of a problem, and twin turbos can alleviate some of the lag at the expense of more plumbing. Intercoolers can reduce the incoming air temperate, at the expense of more plumbing. The problem with emmissions is what caused turbos to fall out of favor during the '90s. STS turbo setups do not have this problem, but have another set of comprimises.

So which one is best? There's no good answer. A DOHC turbo 4 cylinder can end up weighed easily as much as an LS2 once all the intercoolers and plumbing is added on. But the flexibility in component placement may make it well suited for a particular platform. Diesels are well suited for turbos even though they are low revving, because they needs smooth power delivery, and can handle a second for the turbo to spool up and generate the boost. They NEED high compression to run, and are typically in applications where when you need the power, you're going to need it for a good long time, but when you don't, the turbo can let off the boost at idle.

 

[exdeath]

"Twincharging" is using both a turbocharger and supercharger on the same engine, where you have the supercharger to give you torque down low with instant throttle response, while you have a turbo spooling to take over with higher boost and efficiency at higher revs.

 

[Zenmervolt]

Originally posted by: Demon-Xanth
Diesels are well suited for turbos even though they are low revving, because they needs smooth power delivery, and can handle a second for the turbo to spool up and generate the boost. They NEED high compression to run, and are typically in applications where when you need the power, you're going to need it for a good long time, but when you don't, the turbo can let off the boost at idle.

The single biggest reason that diesels are well-suited to turbocharging is that diesel engines have no throttle valve. The intake tract is completely open at all times. Throttle on a diesel is controlled only by the amount of fuel fed into the cylinders. This means that the turbo spools earlier, faster, and stays spooled even between shifts.

ZV

 

[exdeath]

Not to mention you don't have to worry about detonation with diesel and can run like 60 lbs boost on #2 pump fuel.