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-   -   Turbo vs Supercharger (https://www.revscene.net/forums/538254-turbo-vs-supercharger.html)

Lomac 07-09-2008 09:55 PM

Turbo vs Supercharger
 
Turbo

Very few people actually know how a turbocharger works, so below is the best basic description I have ever read. Because building a forced induction set up will require a lot of patience, money and time, you must understand exactly how they work. So to do this, just click on the link below.

How a Turbo Charger works

Remember, turbochargers only work under load.


Different Types of Turbo Chargers
Ball Bearings-Some turbochargers use ball bearings instead of fluid bearings to support the turbine shaft. These bearings are made of very light, but strong material to handle the speeds and temperature of the turbo. They allow the turbine shaft to spin with less friction than the fluid bearings used in most turbochargers. They also allow a slightly smaller and lighter shaft to be used. The lighter the shaft is compared to it's size will help the blades accelerate more quickly, which helps to reduce turbo lag.

Ceramic Turbine Blades-Ceramic turbine blades are lighter than the steel blades used in most turbochargers. Again, this allows the turbine to spin up to speed faster, which reduces turbo lag. The down side is that a ceramic turbine is significantly more prone to shattering.


Twin Turbo
This type of set up uses two turbochargers instead of one. Some of these are often known as a sequential turbo set up. One turbo is smaller, which accelerates quickly in lower rpms, and the larger turbo will take over to produce boost at higher rpm's. Sequential set ups do not always use one very small turbo, and one very large turbo. Sometimes the only difference is one turbo is clipped, or they have different trim levels. Although not all twin turbo set ups are sequential. Some use two identical turbochargers just for the added boost.


Boost Lag
One of the largest downsides of having a turbocharger is boost lag. That means when you step on the gas, the turbo is not instantly creating power. The turbine must speed up to higher rpm's before it starts to create boost. One way to reduce this is to make sure your exhaust flows very well. You can also get properly sized piping.


Properly Sized Piping
Each turbocharger and intercooler use a certain amount of air, you should always try to set up a close ratio of each. One way you have to do this is to have piping that is properly sized. If your pipes are too large, you will have more boost lag because the turbo cannot build the pressure up as quickly. The smaller piping will reduce boost lag, and increase velocity. The problem with smaller piping is that it can choke the engine. You must research this and find a nice medium. The largest concern with the piping is the length. A one by one inch pipe will flow thousands of cfm, but if it's 12 inches long it will only flow a few hundred at most. For the intercooler piping, in general most people use piping thats 25% larger than your compressor output. One of the largest limitations is the throttle body, make sure the throttle body can keep up with amount of air flowing into the engine.


Clipping the Turbo Charger
Clipping the blades on a turbo will allow air to flow through the blades easier, in turn it increases the breathing of the turbo. This means two things, the turbo will breathe into higher rpms, but it will have more boost lag.


Picking the right turbo
Picking the right turbo makes is probably the biggest difference in the way you want your turbocharger set up to work, and how it will actually work. The smaller turbochargers boost up quicker, since there is lass mass there and consumes less air. But, a smaller turbocharger will not make the mass gains in the higher rpm's like a larger turbocharger would. The smaller the turbo, the less boost it makes. The less boost it makes compared to it's potential, the less strain. You have to figure out the proper sized turbo for your car. Remember, sometimes a smaller turbo is not a good choice. The smaller the exhaust side is, the more backpressure there is, which causes more stress on the engine internals. Also, because of the added back pressure there is more heat on the motor. Take in to account how fast you would like to boost, how much power you want to have, if this will be a street set up or a race only car, and your budget. Make sure you consult with someone to this if you do not understand the different trims and turbos, and how they would work with your engine.



The following is a generic wish list for a basic NA to FI (turbo) install:

Collector pipe: pipe that merges front and rear exhaust manifolds and feeds into turbocharger
Turbocharger
Wastegate
Intercooler
Intercooler piping: from turbocharger to IC, from IC to VAF
Blow off valve or compressor bypass valve
Silicone couplers and clamps for intercooler piping
Down pipe: pipe expelling exhaust from turbocharger to cat
Oil lines: Feed line, -4AN; Drain line, at least 1/2
Tapped oil pan: preferably have a female fitting onto the pan
Oil drain flange/gasket: flange that bolts to turbocharger oil drain outlet
FMU: rising rate fuel pressure regulator used to increase fuel pressure according to boost levels
Spare fuel high-pressure hose/clamps: factory size used to connect FMU
Fuel pump: Preferably a 255lph Walbro in-tank pump. Less desirables are the Walbro 190lph and any in-line fuel pump
Vacuum lines, vacuum block/several Ts
O2 sensor bungs (if you replace the log-manifolds with header primaries)

Now here's a basic list of the tools required for a installation.
Piping in a variety of sizes, including elbows, U bends, and straight sections
Chop saw for cutting pipes
Welder for exhaust piping and flanges
Drill with large drill bits for drilling out waste gate, o2 sensor, and blow off valve flange holes
Couplers and clamps for IC piping, oil drain, and fuel lines
Standard and metric sockets, variety of wrench sizes, and standard wrenches
Large scale cutting tools for cutting through front wall and modifying front bumper. (Sawzall, etc)
Other miscellaneous automotive tools for removing and installing basic components

Lomac 07-09-2008 09:56 PM

Supercharger

While understanding how a supercharger works is slightly easier than a turbo, it's still great to learn the basics on what affects what and how to maximize your hard work. The following link will give you a great rundown on the basics of superchargers.

How a supercharger works

Types of Superchargers
Roots -positive displacement units, which means every rev of the blower pumps out a fixed volume of air, regardless of the blower's rpm. Result is that boost comes on instantly. Most applications will produce full boost at 2000-2500rpm. Boost can be increased or lowered by changing pulley size. Best to under drive larger unit than to overdrive smaller one.
Centrifugal- Most popular type for fuel injected engines. Provides airflow proportional to blower rpm, thus full boost comes as high rpm.
Twin-screw- positive displacement, similar to roots. The difference is that this type uses twin screws instead of lobed rotors to compress air, works best when overdriven.


Properly Sized Intercooler Piping
Each Supercharger and intercooler use a certain amount of air, you should always try to set up a close ratio of each. One way you have to do this is to have piping that runs from the intercooler, if chosen to use is properly sized. If your pipes are too large, The smaller piping will mass flow, and increase velocity. The problem with smaller piping is that it can choke the engine. You must research this and find a nice medium. The size of the piping a Supercharger uses is not as delicate as that of the turbocharger, but the velocity must more finely tuned with a Super Charger. The largest concern with the piping is the length. A one by one inch pipe will flow thousands of cfm, but if it's 12 inches long it will only flow a few hundred at most. For the intercooler piping, in general most people use piping that’s 25% larger than your compressor output. The largest limitations is the throttle body, make sure the throttle body can keep up with amount of air flowing into the engine.


Picking the right Super Charger
When considering your Supercharger, you must first decide which of the types you would like to have. This will alter the set up of the unit. Don't pick a Supercharger that is too small or too large. But it is better to under stain a larger unit that it is to overstrain a smaller unit. Also look at how much boost each of the different units creates on a low, and on a high boost pulley. The larger and the heavier the pulley is, the slower it spins, which in turn creates less boost.

!oHenry 07-11-2008 02:47 AM

Good find. I was kinda off about how the turbo worked though. Now i know :)

Gwilo 07-16-2008 10:19 AM

A good book is called Maximum Boost by Corky Bell

The joke is he wrote the book on Turbos

It is on Bentley Press or you can fing here
http://www.bellengineering.net/produ...products_id=17

sirensong 07-16-2008 03:16 PM

Good read, its pretty much spot on from what i can tell.

No matter how much more reliable or whatever pros a super charger has. Nothing's better than a nice fat turbo in my mind. But on the whole Boost is better, no matter what the type.

no_pistons7 07-20-2008 05:31 PM

yea it was a good read. i still prefer a supercharger probably cuz im into domestics but turboing my 5.0 has always been a intrest for me but its much easyer to supercharge i find

Catspider1 08-05-2008 09:59 AM

It rather seems a question of what you are after and on what engine/cylinder arrangement.

FeistyBearH22a 01-03-2009 01:07 AM

http://www.youtube.com/v/Xp-EVOPBhIo&hl=en&fs=1
Here's a cool video about turbo's by Holset.

Supercharger

Pros:
Power on demand.
Con:
Less potential for top end power

Turbo

Pros:
More efficient
More potential for top end power
Cons:
The turbo lag (especially on huge ginormous turbos)
More potential for failure

Leopold Stotch 01-06-2009 09:45 AM

^ without any substantial or even slight information i just assumed that superchargers were more likely to fail. Maybe because the idea of superchargers boggles my mind. it's Magical power!

Berzerker 03-02-2009 08:32 AM

superchargers boggle your mind more than turbo's?? lol. When I try to explain how turbo's work people usually go cross eyed. Superchargers.... easy.

Berz out.

Leopold Stotch 03-04-2009 06:50 PM

Quote:

Originally Posted by Berzerker (Post 6308177)
superchargers boggle your mind more than turbo's?? lol. When I try to explain how turbo's work people usually go cross eyed. Superchargers.... easy.

Berz out.

the technical functionality of a turbo makes sense to me. makes a lot of sense

even DEI makes sense.

Berzerker 03-04-2009 08:26 PM

^^ hahah Supercharged Turbo DEI FTW!!!

Berz out.

eighty8design 11-17-2009 08:40 AM

Great article...finally know how it exactly works!!!!!!

ne14t? 01-12-2010 03:31 PM

Simple way to make your choice

Turbo: Sporadic and non-linear power curve, look at a turbocharged vehicles dyno chart and the power and torque lines look like an earthquake registering on a seismograph.

Supercharger: Smooth and Linear power curve, look at a supercharged vehicles dyno chart and the power and torque lines look smooth and very straight through the RPMs

The effect of both is the same building boost higher then that of the atmospheric pressure entering the engine. The method of producing the power is different with a turbo your not sacrificing power to make power; however your increasing engine bay temps (in some instances depending on the amount of boost you actually increase the efficiency of your engine) But with superchargers your creating boost by running off the crank pulley and anything that runs off your crank pulley will rob your engine of power (not really a significant amount though) and with a supercharger there is less heat created by the boosted air allowing you more lenience with intercoolers and such this is why superchargers are used in carbureted applications for drag racing being less chance to percolate the fuel in the carburetor which is basically the same as detonation in a fuel injected car.

FeistyBearH22a 01-12-2010 04:03 PM

Quote:

Originally Posted by ne14t? (Post 6767059)
Simple way to make your choice

Turbo: Sporadic and non-linear power curve, look at a turbocharged vehicles dyno chart and the power and torque lines look like an earthquake registering on a seismograph.

Supercharger: Smooth and Linear power curve, look at a supercharged vehicles dyno chart and the power and torque lines look smooth and very straight through the RPMs

The effect of both is the same building boost higher then that of the atmospheric pressure entering the engine. The method of producing the power is different with a turbo your not sacrificing power to make power; however your increasing engine bay temps (in some instances depending on the amount of boost you actually increase the efficiency of your engine) But with superchargers your creating boost by running off the crank pulley and anything that runs off your crank pulley will rob your engine of power (not really a significant amount though) and with a supercharger there is less heat created by the boosted air allowing you more lenience with intercoolers and such this is why superchargers are used in carbureted applications for drag racing being less chance to percolate the fuel in the carburetor which is basically the same as detonation in a fuel injected car.

Wow your summary is inaccurate sir. Superchargers have a greater tendency to heat soak because their cooling is essentially limited to heatsink style cooling. Some superchargers have aftercoolers but with increasing heat for the blower decreases the efficiency of the supercharger AND it blows hotter air into the intake manifold. On the other hand increased temps on the turbo especially on the turbine side increases the efficiency of the turbo. If anything superchargers have a higher tendency of detonation duel to the fact that they can't really cool the air going in to the engine properly.

If you want to talk advantages of the using a blower you could have mentioned that blowers are less likely to fail due to the fact that you dont have oil lines and or waterlines to maintain. That in my mind is the only true advantage of a superchargers over a turbocharger.

You like blowers. I get it, but don't post inaccurate information. There is a reason why most car manufacturers now use turbochargers instead of a supercharger in vehicles.

Captain Bondo 01-12-2010 05:26 PM

These discussions always bring out the amazingly biased and uninformed morons of the internet...:)

frojoe 04-07-2010 10:01 PM

Turbo FTW 11.2 times out of 10

Lomac 04-09-2010 07:58 AM

Quote:

Originally Posted by frojoe (Post 6897476)
Turbo FTW 11.2 times out of 10

It's all down to personal preference. I prefer a clutched, twin screw blower over a twin-scroll snail, but others will say the opposite.

KIMBOSLICE 04-28-2010 08:38 PM

Wicked post, but ill stick to my Turbo ;) Vrrrrrooom Pssssssh

nightrider099 05-18-2011 09:50 AM

Hi all i am a new one here i am so happy to join here

Phil@rise 05-18-2011 10:00 AM

Quote:

Originally Posted by ne14t? (Post 6767059)
Simple way to make your choice

Turbo: Sporadic and non-linear power curve, look at a turbocharged vehicles dyno chart and the power and torque lines look like an earthquake registering on a seismograph.

Supercharger: Smooth and Linear power curve, look at a supercharged vehicles dyno chart and the power and torque lines look smooth and very straight through the RPMs

The effect of both is the same building boost higher then that of the atmospheric pressure entering the engine. The method of producing the power is different with a turbo your not sacrificing power to make power; however your increasing engine bay temps (in some instances depending on the amount of boost you actually increase the efficiency of your engine) But with superchargers your creating boost by running off the crank pulley and anything that runs off your crank pulley will rob your engine of power (not really a significant amount though) and with a supercharger there is less heat created by the boosted air allowing you more lenience with intercoolers and such this is why superchargers are used in carbureted applications for drag racing being less chance to percolate the fuel in the carburetor which is basically the same as detonation in a fuel injected car.

Wrong on so many levels. You need to quit lookin to the 70's and 80's for your comparisons.

MojoR32 01-30-2013 07:16 PM

Turbo
 
I'll take turbo any day. You can manipulate exhaust gases a lot easier than belts and pulleys, plus more boost.


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