a coworker of mine has been pestering me since i got my bolt, and i haven't been able to answer his questions satisfactorily.
he wants to know the difference, if any, between a supercharger, blower, and turbo. (and any other type of boost along those lines) i can tell him some things, but lack the technical terms for how they work & what they do.
are there different types of superchargers/blowers/turbos? (e.g.- ours is a "roots" type supercharger, are there any others)?
Could someone explain the differences between them?

i know this is a tall order, but I'm about to ****** a knot in his head if he doesn't quit bugging me.
(i haven't the patience)
thanks in advance..

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brooks
'00 silver "L"

 

Our roots type blowers spin way slower than a turbo; approx 12000 rpm vs. many times more than that for a turbo. Turbos work of exhaust gas where the exhaust gas spins the turbo and if the boost get too out of hand, a waste gate is employed to bleed off boost for the turbo. Turbos are connected to the ehaust manifold of the motor and operate is a very harsh environment. Centrifugal blowers, like the F-body's use spin faster than roots type but, maybe not as fast a turbos. With those you just find a place to put in where a drive belt can spin it and plumb it into the air intake of the motor. All this info is VERY general and my have inaccuracies.

 

see http://www.svt-lightning.com/tech/superchargers.shtml

and http://www.eaton.com/supercharger/whysuper.html

[This message has been edited by Nathan (edited 07-12-2000).]

 

What would make an auto maker chose one over the other, are turbos cheaper I see alot more turbos on vehicles than superchargers.

[This message has been edited by InfiniteMhz (edited 07-12-2000).]

 

Roots type superchargers are great off idle, centrifugal require about 2k rpms before they actually make enough boost. Turbos are known for their efficiency, meaning they require no extra pulley for their operation and they operate off wasted energy (exhaust) and put that energy back towards making the engine put out more power. The draw back to turbos are the fact that they create boost usually above 2k rpms early, and create a lot of heat for the incoming air.

I have heard of a new type of forced induction. I think it was called hydracharger or something. It has the efficiency of a turbo, but not the turbo lag, or the heat associated with one. It also has the boost potential of a supercharger, but can be capable of more rpms. Keep in mind I saw this in an import magazine, but hey its a good idea.

It is essentially a hydralically powered pump that pumps air into your intake. Very efficient, yet very new.

 

What's the difference between a supercharger and a blower?

 

None

Blower is slang

Doug

 

well actually,They are the same but I consider Powerdyne,vortec,paxton=superchargers

Eaton,weiland B+M = Blowers.

I know they are all the same but I look at it like this,Blowers sit on the engine at the intake.Superchargers are the ones which are set on the side driven like an alternator

 

The Supercharger/blower is a parasitic pump -- meaning that it takes horsepower from the engine to turn the pump -- whereas a turbo-charger is generally accepted as non-parasitic -- in that it uses the exhaust that is a natural part of compustion.

The supercharger can maintain a level of boost which is available instantly -- and is noticed immediately off idle -- and is a very quick and predictable way of developing gobs of torque from an engine at low engine rpm.

Turbo-chargers are really two impellers connected together via a shaft -- with two separate air chambers. Exhaust gas spins up the impeller -- which turns the 'pumping' impeller that sucks in fresh air.

The benefit of a turbo is that it automatically adds boost in proportion to the amount of exhaust gas -- up to a pre-determined point -- which is where the waste-gate (dump or vent) limits total output pressure. It is small and light.

For engines which spend a lot of time under load -- but do not need fast throttle response, the turbo is king (used on most heavy truck diesel engines) -- since once it has built up a head of steam, so to speak, it provides boost very efficiently.

The blowers went away with the two-stroke heavy diesel GM engines -- which were the primary users -- in favor of four-stroke diesels and turbo-chargers now popular.

Turbo's are much cheaper to run in all ways, but the instantaneous nature of superchargers is intoxicating.

Ford's little 4-cylinder Thunderbird with turbo was a real sleeper -- it was a bit of a pooch from a throttle-stab from a start -- but once the thing got into second gear, the speedometer maintained or gained speed until your passenger sucked all of the oxygen out of the air and you slowed down.

Both are excellent for maintaining engine power at varying altitudes -- since a naturally aspirated (NA) engine loses some 4 percentage points of power for each 1,000 feet above sea level -- whereas either way of boosting manifold pressure to a constant will maintain engine power at any altitude.

Exhaust gas temperatures are critical with turbos -- which is probably a major factor in the choice of the blower over the turbo for the Lightning.

Yamaha or Suzuki made a turbo-charged 650 (or 750?) in the 80's which was awsome -- but lacked the instant throttle response desired by racers -- and there are aftermarket turbo kits for Honda Motor Homes (Goldwings) that are really small and have turbo speeds somewhere around 20,000 RPM!

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Y2K™

Toreador Red, Keyless XLT SC SB 5.4L E4x4 4wDisc/ABS, 3.73LS, Skid, HD 7700# Towing, LT-245's on Chrome, Tube-Steps, Captain's, 6CD, Tonneau, named: "Nick"

 

Yup blower is slang from the old days when they weren't available on factory engines, only on racers.

I'm kinda like LightningQuick:

Centrifugal- added on aftermarket, to the side and forcing air into the throttle body... Supercharger...

Roots- Factory, DRAWS air thru the throttle body, mounted above/on the intake... Blower...

Both of the above have become interchangeable uses of the terms tho...

Turbo- Exhaust driven...

 

Y2K 7700 4X4:

You are right that there was a brief fascination with turbo bikes in the early/mid 80's, but you might be interested to know that the manufacturers' efforts were a little more widespread than you referenced. Indeed, all four of the major Japanese firms put turbo bikes on the market at that time.

King of them all was the Kawasaki GPZ750 Turbo, which was the first bike (by at least a few weeks) to run in the 10's right out of the crate (10.99 to be exact). This was a two-valve in-line four.

Suzuki offered up the XN85, which was a GS650 (I think a four-valver, definitely an in-line four) with a nice little turbo plumbed up behind the cylinder block. The turbo for the GPZ was in front of the block and down low. I think that most/all of the turbo bikes were also fuel injected, radical for the day (I may be partially/totally mistaken about this). The XN85 got its name from the claimed 85HP output. It was a slug.

Yamaha built the Seca 750 Turbo, which was a four-valve in-line four. The Seca line was reasonably pedestrian (the GPZ was the only turbo bike which was based on anything sporty to begin with), and the addition of the turbo didn't make it a whole lot more exciting.

Honda built the strangest ones - the CX650 and (I think) CX550 Turbos. These were transverse-mounted V-twins (like a Guzzi) with pushrod valve actuation. The non-turbo versions are the bikes that the ghastly Silver Wing was built from. Despite the forced aspiration, you just can't get a 650cc pushrod V-twin to haul ***, and the Hondas also dwelt in the slug domain.

These were the only mass-produced turbo bikes built, to my recollection. There's a lot of activity in the aftermarket these days, with typically spectacular results. Turbo big-bore sportbikes always win the Brute Horsepower Shootout at Daytona, most putting over 300 (and sometimes 400) ponies to the ground from around 1100cc (that would be like your Lightning making 1500-2000 rwhp), and most of them are driven to bike week, not trailered.

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Silver Y2K Lightning
Bone Stock w/ Duraliner, Ford Hitch Cover

Silver (matching) Y2K ML320 Benz
Burl (ML430) Shift ****

Beater 1992 Grand Prix
Commuter Mule

 

Ahhh. Forgot about those. Was still raising teenagers and riding a Harley copy ('82 Yamaha Virago) during that period -- and a friend had what must have been either the Seca or the Suzuki -- whatever it was, it was pretty mild-mannered (boring) and/but had a decent pull in the higher gears.

In fact, it's time to retire the GoldWing next year -- but for the life of me, I don't know what to get (I do ride the kid's modified '99 CBR-900/RR when my arms have shrunken too much due to all of this typing).



<A HREF="http://www.net-link.net/~n8jg/y2k/mvc-018s.jpg" TARGET=_blank> [img]//www.net-link.net/~n8jg/y2k/mvc-018s_small.jpg[/img] </A>


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Y2K™

Toreador Red, Keyless XLT SC SB 5.4L E4x4 4wDisc/ABS, 3.73LS, Skid, HD 7700# Towing, LT-245's on Chrome, Tube-Steps, Captain's, 6CD, Tonneau, named: "Nick"

 

One more question. I understand how the blower forces air into the intake. But does the turbo do the same thing? Or is it hooked up to the engine somehow to increase the RPMs of the engine, thus increasing the horsepower? In other words, how is the power of the spinning turbo transferred to the engine to increase horsepower?

 

the turbo uses exhaust gases to spin a rotor (for lack of the correct word. is it impeller?) which drives intake air into the engine.. so, the more throttle, the more boost... but, you have to wait for the rotor to spin up to get a lot of boost.. that is known as "boost lag" i think.

superchargers - low pressure, instant power
turbos - high pressure, not so instant power
(unless you rev it up a couple grand)

oh.. if i'm wrong on something, flame me horribly..

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brooks
'00 silver "L"

 

Hello all,

What is the difference between a roots-type blower and a screw-type blower.

Thanks in advance,
Jake...