projekt

sounds like nascar and the ban on cams

fc3seeker

why not just get both.

Evil Aviator

"Turbos have 'lost out' only in drag racing probably because most people go to drag races for the noise. Because turbochargers tend to reduce noise, they may never become popular for drag racing."
- Hugh MacInnes

NZConvertible

I've seen it done several times, but in most cases the benefits do not justify the cost and complexity. Making it work properly is harder than you'd think.

totallimmortal

one of the best sounding BOV i have ever heard was on a supercharged civic si, it was a vortec unit and as far as i've heard any supercharger that has piping (not a jacson racing type that bolts on or replaces the intake manifold) can have a BOV

Evil Aviator

A centrifugal supercharger is nothing more than a turbocharger that is run by a belt or gear drive as opposed to an exhaust turbine. That BOV would sound exactly the same if it were on the same engine that had a turbocharger with the same compressor section as the Vortech supercharger. In short, it was the BOV, not the supercharger.

Yes, since a centrifugal supercharger has the same type of compressor as a turbo, you can use a BOV if the system does not use an AFM or MAF sensor upstream of the supercharger. Other superchargers use a bypass valve, which does not vent to the atmosphere, much like the stock RX-7 TII.

The difference in sound between a turbocharger and a supercharger is in the exhaust and drive noise.

edmcguirk

A turbo or a centrifugal supercharger usually blow into the throttle. The roots supercharger usually sucks through a throttle. Also a roots supercharger has a constant boost (approximately) while a turbo or a centrifugal supercharger have rising rates of boost.

So roots superchargers really never should have a BOV. A turbo can have a BOV to keep the blades spinning. A centrifugal can have a BOV but doesn't really need one.

ed

Evil Aviator

http://www.superchargersonline.com/content.asp?id=14

RXSevenSymphonies

iTrader: (2)

The Battle Of The Boost

http://home.comcast.net/~maynard5000...d/hotrod1.html

vectorminds

That review seems a little limited... mainly because they used a holly blower... which is about as archaic as the camden blower...

It would be really nice to see a comparison between a turbocharger setup and a whipple that are each well tuned and producing the same amount of hp... and then compare the torque curves to see which would actualy be faster.

Because in my mind the only two options would be turbo or whipple... roots is out because its far too inneficient, centrifugal is out because its all the worst parts of a turbo setup without any of the benefits.

Whipples and turbos on the other hand have near the same efficiencies... with whipples possibly heating the intake charge less than the turbo. Both have excelent high end boost response, however the whipple should build boost faster.

I don't know if a comparison has ever been done (even better if its on a rotary) between a whipple and a turbo making the same peak power... but thats what we really need.

Blake_91

I understand what you are trying to ask.
None the less I have to be a picky little bitch and inform you that a turbo is a "supercharger". Thats right turbo=supercharger!
Wow... thats going to start one huge bitch slap among the mechanicly challenged!
Blower vs turbo... would be more correct.

Just informing,
-Blake

Damn I hate people that have to go and get all technical, especially when they know what a person was trying to say!

*TURBO*

totallimmortal

ok blake so whats the difference in a supercharger and a blower? Because i know for a fact that all the muscle car guys call them both,
Turbo and Supercharer both = forced induction, supercharger or blower is belt driven, turbo is exhasut driven nothing with a belt is technicaly called a turbo

Evil Aviator

Actually, that is not correct. The correct terminology would be Supercharger vs. Turbosupercharger, but the title of this thread uses the perfectly acceptable shortened form, "turbo", and he could have also used the other acceptable shortened form, "turbocharger". I think that it is safe to say that nobody on this forum thinks that the word "turbo" applies to marine snails with respect to this thread. Technically, the term "blower" applies only to superchargers that have an external compression ratio rather than an internal compression ratio, which means that the term does not apply to Lysholm or centrifigual superchargers. Wow... thats going to start one huge bitch slap among the mechanicly challenged!

Blake_91

Seems how you didn't understand what I was trying to say... Ill try again!
1) a turbo charger is a supercharger
2) a blower is a supercharger
3) allthough supercharger is commonly used as a satisfactory replacement word/term for blower, technicly it is still incorrect.
here is how websters explains it, just incase it might help you understand...
Main Entry: su·per·charg·er
Pronunciation: -"chär-j&r
Function: noun
: a device (as a blower, turbo or compressor) for pressurizing the cabin of an airplane or for increasing the volume air charge of an internal combustion engine over that which would normally be drawn in through the pumping action of the pistons.

I'll ask my ASE certified master auto technision father today, just to make sure that I am not speaking out of my ***. Seriously I would hate to be leading people astray. I will be the first one to admit being wrong if I am! I am not a self richous *****... I love to learn... so if I am wrong, Let me know how/why you think so?
Remember a "supercharger" by definition is anything that charges/forces more air into your combustion chamber.
:quote:The correct terminology would be Supercharger vs. Turbosupercharger
This statement allthough "acceptable..." Is more correctly stated as:
Blowersupercharger vs. Turbosupercharger. Why? Because they are both "superchargers".

-Blake

BTW... Thanx for singeing a hair on my pinky toe?

:Edit: Felt left out, thought I needed to add my own little immature smilly!

White Tiger

ok ok everybody untwist your panties, cause i am going to throw a monkey wrench in to twist your brain.

there a two common types of superchargers: centrifugal and roots-type.

turbos fall into the centrifugal category while the belt driven blower falls into the roots-type category.

but there are also belt driven centrifugal superchargers, such as the " vortec " which utilizes the compressor side of a turbo but drives it with a belt.

side note: all two stroke engines are supercharged... how can this be?... take a motorcycle engine as an example, the piston on its down stroke pressurizes the air in the case and forces it into the combustion chamber at more than atmospheric pressure...thus by definition it is supercharged...nice monkey wrench huh

BTW...blake is correct

Evil Aviator

Correct, although "turbo charger" is supposed to be written as one word, "turbocharger", which is short for the technically-correct term of "turbosupercharger".

Correct, a blower is a type of supercharger, assuming that the blower in question raises the air pressure. If the blower does not increase the air pressure, then it is just a blower, not a supercharger.

Technically, the word "blower" only applies to superchargers that do not have an internal compression ratio. However, it is commonly used as slang to describe all superchargers, even though this is not technically correct.

The word "blower" describes an air mover, not a compressor. This is why "blower" technically applies to superchargers that do not have an internal compression ratio, as well as cooling fans, air conditioning impellers, and other types of air movers.

This subject is actually a little out of his realm (SAE as opposed to ASE), but he probably knows where to look it up, and he will be able to explain it to you better than some lame internet forum post.

Evil Aviator

Actually, there are 3 common types of superchargers. You forgot the Lysholm (twin screw). I think the Lysholm will gain popularity as advances in machining reduce the production cost.

Although most automotive turbos are centrifugal, they can also take other forms. The "turbo" term simply means that the supercharger is driven by a turbine, and has absolutely no bearing on the compressor or blower design. If you replaced the drive pulley of a Roots blower with a turbine, it would become a turbosupercharger (aka turbo). If you replaced the turbine of a turbocharger with a drive pulley, it would become a supercharger (ie a plain supercharger as opposed to a turbosupercharger).

LOL

Have you seen the Miller cycle engine?
http://www.mazda.com.au/articleZone....ticleZoneID=92

edmcguirk

The difference between a Lysholm SC and an Eaton SC with twisted rotors and V shaped outlet port is real but it's almost more of a patent issue than a real preformance issue.

Roots type SC's can have internal compression, they just need to make outlet port smaller. A straight lobed SC will leak back past the lobe seals but a twisted lobe SC has more lobes between the intake and output.

And besides, most of the efficiency difference between any super/turbo/whatever-charger can be compensated by a slightly more efficient intercooler.

ed

edmcguirk

I don't know if there are any water jackets or other features in the way but technically you could make a Miller Cycle Rotary engine.

hmmm

ed

Blake_91

The word "supercharger" can be used to describe anything that induces more than atmospheric preasure into the engine.

:quote:"If the blower does not increase the air pressure, then it is just a blower, not a supercharger."
This makes no sense. I have never seen a blower that dosent increase the "air pressure". What purpose would it serve? It would add wieght, labor the engine and, shoot the air that you've just supercharged around the engine bay? Seems how blowers do increase the amount of air, above that of atmospheric pressure, they are "superchargers". Blowers "supercharg" air into your combustion chamber. Turbo's "supercharg" air into your combustion chamber. This said they are both "superchargers". Therefor when you say, supercharger vs turbosupercharger? I say what kind of supercharger vs turbosupercharger? Because the word supercharger can be used to describe anything that forces air into your combustion chamber, not just a belt driven setup.

Technicly I could take a super high powered "electric" 4" fan and fit it into the intake snorkle of my car, as long as it forces more than atmospheric pressure into my combustion chamber... its "supercharged".

:quote:"Correct, a blower is a type of supercharger"
And a turbo is a type of supercharger.
So, if I say I have a supercharger on my car, where is the designation that implies what kind of supercharger it is? Turbo/blower...etc...?

When you say turbo... You've designated what kind of a supercharger your talking about, so that is all good. When you say Supercharger... Great, you have told me what it is that your setup does, but you still hav'nt designated what kind of supercharger/setup your talking about!

-Blake
BTW: Tanx fer corecting me "typo"!

CypherNinja

Guess again. A less efficient compressor will heat the intake charge more. While this heat is relatively easy to deal with via intercooler, care to take a wild guess where it came from? Funny, I though it manifested itself as extra hp needed to drive the supercharger or as extra backpressure in a turbo. Conservation of energy, man.

edmcguirk

True, you can't get all of the efficiency back with a better intercooler but you can come close enough.

Very very few people can get the last 10% out of their engine. Few people even want to make the sacrifices or the narrow focus that would take.

Not to mention the very very very few who can do it without blowing up at least a few engines.

ed

projekt

thanks aviator, i couldn't ever find the info on that design. it seems similar in theory to the saab design recently of a tilting cylinder head to lower the CR while on boost.

so technically, the V6 in the millenia is just a KL with very retarded intake timing and a blower?

DEZERTE

I know this thread is kinda old, but how would getting true duals be comparable to any form of forced induction.. wtf?

casio

hahaha. that pretty funny. anyone care to prove the "tru duals" theory? they might end up accidentally proving themself wrong. uh oh !