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Can someone explain how the supercharger increases power? A turbocharger uses exhaust pressure to spin the turbine, which is energy that would otherwise be lost as heat. But the supercharger is belt driven from the crankshaft. It seems to me that the energy gained by compressing the intake air would be offset by the load on the crankshart to spin the supercharger. You can't just make free energy. Remember the 1st Law of Thermodynamics?
 

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Vrooom
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Simple answer....

The super charger pumps more air into the engine and at the same time more fuel is added - thus more umph. The extra umph caused by the extra fuel air more than compensates for the extra load the super charger puts on the crank.
What's more there no 'turbo lag' with a super charger and the extra torque starts at a lower RPM.

But overall a turbo charger is more efficient as it uses 'wasted' energy from the exhuast.
I'm sure some on else could give a more detailed technical answer, this is the 'simple answe'.

BTW I have MCS (super-charged) and 911 Twin Turbo - both drive differently and personally I prefer the feel of the turbos as they spool up the boost :)
 

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-Nathan said:
But the supercharger is belt driven from the crankshaft. It seems to me that the energy gained by compressing the intake air would be offset by the load on the crankshart to spin the supercharger. You can't just make free energy. Remember the 1st Law of Thermodynamics?
Overall you gain more than you lose. YOu gain more power than you lose with the offset of driving the Compressor with the engine.

And you're right you cant make free eneregy... same goes for the Turbo... and not i'm not talking about just the turbo lag...
 

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Turbo lag is a thing of the past anyway, If anybody is still getting turbo lag these days its either on a carby dinosaur or they have the wrong size turbo or its set up for drags. A correctly sized turbo and proper management system and there is no lag to speak of.

Actually both my turbo's come on boost must faster than my Supercharger.
 

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XTREEM said:
Turbo lag is a thing of the past anyway, If anybody is still getting turbo lag these days its either on a carby dinosaur or they have the wrong size turbo or its set up for drags. A correctly sized turbo and proper management system and there is no lag to speak of.

Actually both my turbo's come on boost must faster than my Supercharger.
No, turbo still isnt the thing of the past just yet... have you driven a Saab lately? The turbo lag on that thing was horrible... i forget which model it was... a 9-5 aero or a 9-3... I didnt like it at all...

Both your turbos are faster than your Supercharger? thats GREAT! what do you have? a 996 Turbo?
 

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EBMCS03 said:
No, turbo still isnt the thing of the past just yet... have you driven a Saab lately? The turbo lag on that thing was horrible... i forget which model it was... a 9-5 aero or a 9-3... I didnt like it at all...

Both your turbos are faster than your Supercharger? thats GREAT! what do you have? a 996 Turbo?

I didnt say they are faster than my S. They are anyway , but what I said is they boost much faster than the supercharger. I have a GT28 ball bearing turbo on a 2litre Hyundai Beta engine and it boosts straight off idle and is pushing 20 pound very quickly, and a T3/T4 hybrid on a CA18 DET with much the same results.
 

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XTREEM said:
I didnt say they are faster than my S. They are anyway , but what I said is they boost much faster than the supercharger. I have a GT28 ball bearing turbo on a 2litre Hyundai Beta engine and it boosts straight off idle and is pushing 20 pound very quickly, and a T3/T4 hybrid on a CA18 DET with much the same results.
Oh no.. I didnt necessarily mean the car... I ment your turbo spools up faster than the supercharger... but I thought... maybe... since it spools up faster it can be a Porsche Turbo :D
 

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The turbo's on most Saabs are low pressure turbos, not there for pure extra power.

Turbos are not a think of the past, actually superchargers are, they've been around longer.

We'll all be driving turbos soon - Diesel twin turbos. ;)
 

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Your turbo might produce boost quicker. Close the bypass valve on the Eaton and it's producing boost full time.
It all depends on design and implementation.
They each have design limitations. The current trend towards dual stage turbos is an indicator of their limitation.
Same thing for clutch driven or viscous coupled superchargers. Just another way to circumvent the physics of each design.


Back to the original question

Read this link





BTW. Technically a turbocharger is a supercharger.
 

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obehave said:
Your turbo might produce boost quicker. Close the bypass valve on the Eaton and it's producing boost full time.
It all depends on design and implementation.
They each have design limitations. The current trend towards dual stage turbos is an indicator of their limitation.
Same thing for clutch driven or viscous coupled superchargers. Just another way to circumvent the physics of each design.


Back to the original question

Read this link





BTW. Technically a turbocharger is a supercharger.
Yeah I'm not trying to argue which is best, simply stating that people that continue to describe turbo's as having "LAG" would probably be surprised if they are still comparing late model turbo's to older ones. The supercharger will still boost faster if say you booted them both at 80km in fourth gear but in a drag race the turbo would kill it.

Just to clear something up everybody seems to think I said "turbo's are a thing of the past" but I said "turbo LAG is a thing of the past" Turbo is still the future.
 

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Even with the most advanced turbo system....

there will always be some 'turbo lag' the question is can the driver notice it ?
With most modern systems the answer is usually no.
However on my '03 911 TT I can detect a small amount of lag largely because the turbo's don't produce significant boost until the engine is over 2500rpm - whereas with a belt driven super charger you can have boost from the outset.

But I agree - turbo charging is the way of the future and I certainly like the extra push in the back when those babies do their stuff :)
 

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timf said:
there will always be some 'turbo lag' the question is can the driver notice it ?
With most modern systems the answer is usually no.
However on my '03 911 TT I can detect a small amount of lag largely because the turbo's don't produce significant boost until the engine is over 2500rpm - whereas with a belt driven super charger you can have boost from the outset.

But I agree - turbo charging is the way of the future and I certainly like the extra push in the back when those babies do their stuff :)

Yeah there will always be some as you pointed out but under 2500rpm is nothing as far as I'm concerned, thats 1500rpm over idle ;) a slight slip of the clutch. :D
 

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Erm.... "turbo lag" is generally understood to be the delay between stamping on the accelerator pedal and the car taking off for the horizon.

The speed at which the engine has to be turning before the turbo is spinning fast enough to make significant boost is something else.

That said, small turbos (assuming they are correctly plumbed in) spin up at lower engine rpm than larger ones.
 

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Mike Edwards said:
Erm.... "turbo lag" is generally understood to be the delay between stamping on the accelerator pedal and the car taking off for the horizon.

The speed at which the engine has to be turning before the turbo is spinning fast enough to make significant boost is something else.

That said, small turbos (assuming they are correctly plumbed in) spin up at lower engine rpm than larger ones.

One & The Same.
 

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Yes and no.

The 1st you can eliminate through dump valves etc.

The second requires the use of either a very small turbo or more than one.

To experience the difference on a particular turbo install, find a steep hill and start driving up it at low speed in a sufficiently high gear that the turbo isn't spinning fast enough to provide significant boost. Nail the throttle.

You will - eventually - get up the hill, but there won't be any "lag" to speak of.

Do the same thing but use 1st gear.

The car will take of like a scalded cat* when you nail it, but - depending on the nature of the install - there may or may not be any "lag" between the two.

A mechanically driven supercharger will behave the same way as the turbocharger in the first case, but will never suffer from the "lag" that may be experienced with the turbocharger in the second case.

*Note to overseas readers: This is a figure of speech - Brits are not in the habit of scalding cats!
 

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Well turbo lag has been eliminated is the cry from turbocharger fans for almost as long
as the turbo has been in common use. I'll agree you can't put a stop watch to it but
there is something in the brain that detects any delay and it makes the engine feel
disconnected to the throttle. Which can be ironic as many turbos have a direct connection
while many normally aspirated cars now have electronic throttles. I'm not a skilled driver but
I will happily pay extra for a normally aspirated engine with sharp throttle response over one
with an average throttle response. So for me and many others turbos still don't cut it. Having
said that I don't think the S's throttle response is anything to write home about if you have
been cruising for a while and have low quality petrol in it but at least we know the solution
:D .

p.s. I'm happy to reconsider my opinions if anyone wants to loan me their 996 Turbo ;) .
 

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BHP per litre for a given fuel a turbocharged car will has potential to yield more power
than any other means. Although not completly ' free power' it is considerably more efficient
than a supercharger. Regards Roland Gt Tuning
 

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I'd go with that. Current car is a Golf GTI 1.8T (Tuned to 200hp)
There is lag, but its very minor and I actually rather like the build up, it feels great! Once the car is over 2000rpm there's no lag. Just torque and 270NM of it :D Very quick car, quicker than a CooperS. And my fuel consumption is WAY better than what MINI quote for the Cooper S's (although figures are usually a load of crap)
Pre-tuning there was practically no lag on the Golf, it just felt like a larger engine which is what VW intended.

Turbos are the way forward I'd say. VW's 1.8T is a fabulous engine. Their new 2.0T is apparently even better, again, very little lag, just lots of torque.

However, scrub that and roll on March! My CooperS arrives :D Took it for a test drive and I loved the sound of the Supercharger and to be honest in terms of delivery it was very similar to the Golf. Exceptionally smooth and torquey when driven normally and fantastic with the right foot down!
Just the Mini was far more fun to drive than the Golf and thats what matters ;) Plus I have to go through life and say I owned a Supercharged car!!
 

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Motor Trend had an article about the Top Fuel Dragster.

They make approx 7800 Horsepower.

That's 975 Horsepower per cylinder

It takes 900 Horsepower to turn the supercharger.

The motors rev to around 8,000 rpm.

In the quarter mile, the motor turns over 869 times!

It pulls 5 Gs starting and 6 Gs when the chuts open.
 
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