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Old 01-27-2016, 06:58 AM   #21
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I asked him if he was running a HUGE a/r and low low boost.

Would it even be theoretically possible this way?
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Old 01-27-2016, 10:22 AM   #22
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nope
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Old 01-27-2016, 10:26 AM   #23
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What is the power ouput that he's claiming with this magical setup?
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Old 01-27-2016, 04:07 PM   #24
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You stopped too late. First stop should have been conservation of mass. He's probably referring to Bernoulli and that's conservation of energy.
Maybe some of that mass turns into energy!
E=mc^2 you know!!
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Old 01-27-2016, 04:20 PM   #25
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Originally Posted by JasonC SBB View Post
Maybe some of that mass turns into energy!
E=mc^2 you know!!
Which is, of course, how the law of conservation of mass was ultimately proven to be wrong. So either way he was wrong starting with word #3
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Old 01-27-2016, 04:22 PM   #26
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The turbo kit is called "Alfabert Omegastein II" with optional doodoo box and every part comes in a separate box over a period of 3 years.
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Old 01-27-2016, 04:25 PM   #27
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Upgrade to "Supernova" for the low-low price of a few trillion tons of hydrogen.
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Old 01-28-2016, 03:00 AM   #28
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Originally Posted by Savington View Post
Stopped reading right there. The whole point of the larger exhaust is to increase flow rate.
I guess I was up too late. Anyway I'm just trying to break down the concept to see where the 2.5" would be advantageous. By what means does the larger pipe allow increased flow rates? The damn title of this thread has theory in it after all...

EDIT: WHO TOOK MY CAT AWAY!?
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Old 01-28-2016, 04:04 AM   #29
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...By what means does the larger pipe allow increased flow rates? ...
The turbine on the turbo is extracting energy from the exhaust to drive the compressor. The total amount of thermal energy in the exhaust is called enthalpy. The amount of energy at any given point is the mass flow times the enthalpy. Energy = mass flow x Enthalpy

The change in enthalpy across the turbine is how much energy the turbine extracted from the exhaust. You want to maximize this to make it spool faster. It takes a certain mass flow to spool the turbo, the quicker you get that mass flow, the sooner you get boost.

A larger exhaust pipe after the turbine lowers the pressure on that side of the turbine. The bigger the pipe, the lower the pressure will be. This improves the flow in the system, so mass flow goes up at any given boost pressure. So more mass flow everywhere from spooling to redline.

This has two big benefits. Time to boost is shorter, and power at a given boost level will be higher. Smaller benefit would be reduced turbine inlet pressure, which will make the motor slightly more knock resistant too due to less internal EGR.
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Old 01-29-2016, 10:43 PM   #30
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Originally Posted by patsmx5 View Post
The turbine on the turbo is extracting energy from the exhaust to drive the compressor. The total amount of thermal energy in the exhaust is called enthalpy. The amount of energy at any given point is the mass flow times the enthalpy. Energy = mass flow x Enthalpy

The change in enthalpy across the turbine is how much energy the turbine extracted from the exhaust. You want to maximize this to make it spool faster. It takes a certain mass flow to spool the turbo, the quicker you get that mass flow, the sooner you get boost.
.
Work through the system would be = Mass flow x Enthalpy through the turbine - the abs value of the Mass flow x Enthalpy through the compressor;

You also want to minimize the work that the compressor has to do, it is a small amount but if you can optimize this there are gainz to be had. Also the pressure ratio of the turbine is directly related to the temperature, if you can increase the temp prior to the turbine you can increase the delta of the enthalpy which will give you more power. Yet we are a bit limited on a metallurgical level here as melting pistons and such is no fun.
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Old 02-28-2016, 04:56 PM   #31
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from what i always understand. bigger will give you more top end, and better peak hp....smaller, but not too small will give you better low end
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Old 02-28-2016, 04:57 PM   #32
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Originally Posted by gtiracer06 View Post
from what i always understand. bigger will give you more top end, and better peak hp....smaller, but not too small will give you better low end
That's wrong.
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Old 02-28-2016, 05:59 PM   #33
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from what i always understand. bigger will give you more top end, and better peak hp....smaller, but not too small will give you better low end
Pat just explained it
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Old 02-28-2016, 06:08 PM   #34
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Originally Posted by gtiracer06 View Post
from what i always understand. bigger will give you more top end, and better peak hp....smaller, but not too small will give you better low end
No. Please stop regurgitating this garbage.
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