New supercharger kit
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From: Sydney
Originally Posted by trivium,Nov 2 2006, 05:44 AM
Im sorry, I forgot this was a public forum. How rude of me.
Oh, you apparently already know this.
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From: Gie
Originally Posted by Soul Coughing,Nov 1 2006, 03:11 PM
a roots style supercharger uses more energy to spin than a centrifugal supercharger... (what it gives up in efficiency it gives back in a flat low end torque curve) my last car had one.... just like the centrifugal supercharger it has a bypass valve that drops the boost when cruising... but it is still using engine power to spin the supercharger no matter what design... unless its a mercedes design with a A/C style clutch to disengage the S/C when cruising.
At full load a centrifugal compressor will be more efficient than a roots style blower. But how often are you at full load? Depending on your driving style and driving location, I'd guess 1-10%?
You can throw a bypass valve on a centrifugal supercharger but you cannot stop the fact that it is always compressing the air in it's housing through internal compression. In bypass mode, roots chargers hardly draw any power at all. The design itself dicates that they cannot compress air on their own, and when not at high load, the more or less free-wheel. They are merely "air movers" and not "air compressors". For this reason, they are also less efficient under full load.
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From: The Beach, CA
Correct, the roots types do not actually compress the air which is really the biggest functional difference between them.
I wrote this a while back which is pretty easy to understand:
http://www.s2000turbo.com/index.php?option...id=91&Itemid=27
The kits are actually not completed yet but should be soon. There will be variable sizes and kits available.
I wrote this a while back which is pretty easy to understand:
http://www.s2000turbo.com/index.php?option...id=91&Itemid=27
The kits are actually not completed yet but should be soon. There will be variable sizes and kits available.
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Joined: Mar 2004
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From: Slovakian living in Dubai
Originally Posted by trivium,Nov 1 2006, 02:47 PM
Centrifugal kits develop power when you are within the power range. Didnt you know that?
There is no system that "has boost when running 80 on the highway at 4k rpm". Boost is not created by the SC or the turbo but by the resistance of the intake manifold.Try to blow into a straw with open end and into one with a squeezed end
Since you bleed the boost off with a valve (bypass or blow off) during cruizing ('power range" or not) you are NOT boosting.
BTW where does the "power range" start ?
Here?
To sum it up:
A turbo has a BOV so it does not boost while cruizing.
A SC has a bypass valve so it does not boost while cruizing.
And you have oversmart comments so we consider you an a$$.
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Originally Posted by jakub2000,Nov 2 2006, 12:00 AM
What has "developing power" and "powerrange" to do with boosting while cruizing?
There is no system that "has boost when running 80 on the highway at 4k rpm". Boost is not created by the SC or the turbo but by the resistance of the intake manifold.Try to blow into a straw with open end and into one with a squeezed end
Since you bleed the boost off with a valve (bypass or blow off) during cruizing ('power range" or not) you are NOT boosting.
BTW where does the "power range" start ?
Here?
To sum it up:
A turbo has a BOV so it does not boost while cruizing.
A SC has a bypass valve so it does not boost while cruizing.
And you have oversmart comments so we consider you an a$$.
There is no system that "has boost when running 80 on the highway at 4k rpm". Boost is not created by the SC or the turbo but by the resistance of the intake manifold.Try to blow into a straw with open end and into one with a squeezed end
Since you bleed the boost off with a valve (bypass or blow off) during cruizing ('power range" or not) you are NOT boosting.
BTW where does the "power range" start ?
Here?
To sum it up:
A turbo has a BOV so it does not boost while cruizing.
A SC has a bypass valve so it does not boost while cruizing.
And you have oversmart comments so we consider you an a$$.
The sand must be getting in your food.
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Joined: Jul 2005
Posts: 1,670
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From: Gie
Originally Posted by kane.s2k,Nov 2 2006, 01:38 AM
Correct, the roots types do not actually compress the air which is really the biggest functional difference between them.
I wrote this a while back which is pretty easy to understand:
http://www.s2000turbo.com/index.php?option...id=91&Itemid=27
The kits are actually not completed yet but should be soon. There will be variable sizes and kits available.
I wrote this a while back which is pretty easy to understand:
http://www.s2000turbo.com/index.php?option...id=91&Itemid=27
The kits are actually not completed yet but should be soon. There will be variable sizes and kits available.
The Roots heat generation is largely due to inefficiencies in the design, in that it causes the air to "crash" together upon exiting the lobes.
I'll post come CFD images shortly. Pretty sexy stuff...
From your site:
The twin screw also differs from the roots in that the rotors do not ever actually touch which reduces wear and friction (heat) greatly.
