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slam
11-13-2003, 04:44 PM
What is better a turbo or a supercharger and can any1 tell me the difference between them i know one is at the idle till the redline and one has to crank up a little what one is what i need it to be a every day can that can do 12-13s

k20hatch
11-13-2003, 04:56 PM
This should be under the engine forum..:confused:

2k2SiAutoXer
11-13-2003, 05:16 PM
well, you could start off by reading under the engine forum AND doing a search. there has been a lot of discussion about this. For the times your looking for you would want to go turbo. Also I think youare looking a little fast as far as times go, esp if you dont know much about f/i. Start small then work your self up. Hope this helps.

--Tom

Mugen_EP
11-13-2003, 05:23 PM
:m:

ep3guy
11-13-2003, 06:13 PM
Just buy my turbo, still brand new never used. Letting it go CHEAP, check the classifieds.

BlackNRedSi
11-14-2003, 09:20 AM
here you go...the power of GOOGLE always helps bra!

eric
_____

A supercharger is mounted to the engine and is driven by a pulley that is inline with the crank (or accessory) belt. Air is drawn into the supercharger and compressed by either an impeller (centrifugal-style supercharger), twin rotating screws (screw-type supercharger), or counter-rotating rotors (roots-type supercharger). The air is then discharged into the engine's intake. Faster crank speed (more engine rpm) spins the supercharger faster and allows the supercharger to produce more boost (normally 6 to 9 psi for a street vehicle). Typical peak operating speeds for a supercharger are around 15,000 rpm (screw-type and roots style superchargers) and 40,000 rpm (centrifugal-style superchargers).

A turbocharger operates in much the same way as a centrifugal (internal impeller) supercharger, except it is not driven by pulleys and belts attached to the engine's crank. A turbo is instead driven by exhaust gasses that have been expelled by the engine and are travelling through the exhaust manifold. The exhaust gas flows through one half of the turbocharger's turbine, which drives the impeller that compresses the air. Typical operating speeds of a turbocharger are between 75,000 and 150,000 rpm.

Now it's time to evaluate the turbocharger versus the supercharger according to several important factors.

Cost
The cost of supercharger and a turbocharger systems for the same engine are approximately the same, so cost is generally not a factor.

Lag
This is perhaps the biggest advantage that the supercharger enjoys over the tubo. Because a turbocharger is driven by exhaust gasses, the turbocharger's turbine must first spool up before it even begins to turn the compressor's impeller. This results in lag time which is the time needed for the turbine to reach its full throttle from an intermediate rotational speed state. During this lag time, the turbocharger is creating little to no boost, which means little to no power gains during this time. Smaller turbos spool up quicker, which eliminates some of this lag. Turbochargers thus utilize a wastegate, which allows the use of a smaller turbocharger to reduce lag while preventing it from spinning too quickly at high engine speeds. The wastegate is a valve that allows the exhaust to bypass the turbine blades. The wastegate senses boost pressure, and if it gets too high, it could be an indicator that the turbine is spinning too quickly, so the wastegate bypasses some of the exhaust around the turbine blades, allowing the blades to slow down..
A Supercharger, on the other hand, is connected directly to the crank, so there is no "lag". Superchargers are able to produce boost at a very low rpm, especially screw-type and roots type blowers.

Efficiency
This is the turbo's biggest advantage. The turbocharger is generally more economical to operate as it as it is driven primarily by potential energy in the exhaust gasses that would otherwise be lost out the exhaust, whereas a supercharger draws power from the crank, which can be used to turn the wheels. The turbocharger's impeller is also powered only under boost conditions, so there is less parasitic drag while the impeller is not spinning. The turbocharger, however, is not free of inefficiency as it does create additional exhaust backpressure and exhaust flow interruption.

Heat
Because the turbocharger is mounted to the exhaust manifold (which is very hot), turbocharger boost is subject to additional heating via the turbo's hot casing. Because hot air expands (the opposite goal of a turbo or supercharger), an intercooler becomes necessary on almost all turbocharged applications to cool the air charge before it is released into the engine. This increases the complexity of the installation. A centrifugal supercharger on the other hand creates a cooler air discharge, so an intercooler is often not necessary at boost levels below 10psi. That said, some superchargers (especially roots-type superchargers) create hotter discharge temperatures, which also make an intecooler necessary even on fairly low-boost applications.

Surge
Because a turbocharger first spools up before the boost is delivered to the engine, there is a surge of power that is delivered immediately when the wastegate opens (around 3000 rpm). This surge can be damaging to the engine and drivetrain, and can make the vehicle difficult to drive or lose traction.

Back Pressure
Because the supercharger eliminates the need to deal with the exhaust gas interruption created by inserting a turbocharger turbine into the exhaust flow, the supercharger creates no additional exhaust backpressure. The amount of power that is lost by a turbo's turbine reduces it's overall efficiency.

Noise
The turbocharger is generally quiter than the supercharger. Because the turbo's turbine is in the exhaust, the turbo can substantially reduce exhaust noise, making the engine run quieter. Some centrifugal superchargers are known to be noisy and whistley which, annoys some drivers (we, however, love it!)

Reliability
In general, superchargers enjoy a substantial reliability advantage over the turbocharger. When a a turbo is shut off (i.e. when the engine is turned off), residual oil inside the turbo's bearings can be baked by stored engine heat. This, combined with the turbo's extremely high rpms (up to 150,000rpm) can cause problems with the turbo's internal bearings and can shorten the life of the turbocharger. In addition, many turbos require aftermarket exhaust manifolds, which are often far less reliable than stock manifolds.

Ease of Installation
Superchargers are substantially easier to install than a turbos because they have far fewer components and simpler devices. Turbos are complex and require manifold and exhaust modifications, intercoolers, extra oil lines, etc. - most of which is not needed with most superchargers. A novice home mechanic can easily install most supercharger systems, while a turbo installation should be left to a turbo expert.

Maximum Power Output
Turbos are known for their unique ability to spin to incredibly high rpms and make outrages peak boost figures (25psi+). While operating a turbocharger at very high levels of boost requires major modifications to the rest of the engine, the turbo is capable of producing more peak power than superchargers.

Tunability
Turbochargers, because they are so complex and rely on exhaust pressure, are notoriously difficult to tune. Superchargers, on the other hand, require few fuel and ignition upgrades and normally require little or no engine tuning.


While the supercharger is generally considered to be a better method of forced induction for most street and race vehicles, the turbo will always have its place in a more specialized market. Superchargers generally provide a much broader powerband that most drivers are looking for with no "turbo lag". In addition, they are much easier to install and tune, making them more practical for a home or novice mechanic.

fishboy
11-14-2003, 11:06 AM
actually check out honda-tech's forced induction forum. you will learn alot.

TrippZ
11-14-2003, 01:16 PM
you should be in the 13's with the cybernation kit with intake and exhaust clutch flwheel and other basics.

ep3guy
11-14-2003, 05:37 PM
I think the post above is a biased opinion favoring a supercharger. Go to honda-tech and do a search in the forced induction section and you'll find a lot of useful info.

myeverlovinsir
11-14-2003, 06:09 PM
I remember reading that a long time ago. I agree that it may seem bias towards SC but each point is valid. Turbo is not for any novice tuner and would love to get more hands on experience. Turbo by most first time installers is somewhat of a black art when it comes to getting it right. It has been said "A little knowledge is a dangerous thing." You can never have enough knowledge.