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Old 02-19-2010, 09:37 AM   #1088 (permalink)
RCZ
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Quote:
Originally Posted by KEVTEX View Post
With a turbo, the engine has to work harder to get the exhaust out because of the increased back pressure the turbo provides. The same amount of extra work is required if you take the power from a crank pulley.
Not at all because the sc has to move gearing and a belt while the tc only has to spin. We aren't arguing for the sake of argument, we know this is and has always been the case. In modern days, parasitic losses from the sc have been greatly reduced through new designs, but its still takes a bigger toll on the engine to make the power.


Also, guys, the whole bigger turbo makes more power thing.... From what I understand its not because it flows more, we know that 5psi is 5psi. What matters is the charge density of that 5psi. According to what Silo posted, a turbo that is in its peak efficiency zone (or island if you've ever seen a turbo flow chart) will create a more dense 5psi than one that is not. Think of it this way... colder air is denser, air particles are more compact therefore there is more oxygen to burn therefore you make more power. The same apparently goes for a turbo operating at peak efficiency vs one that isnt. The one operating at peak eff. somehow produces a more dense charge (at the same temperature) as the one that is out of its efficiency zone.

The post by silo didnt explain why, but I have a feeling it has something to do with how the air is compressed in a more efficiently sized tc than a less efficiently sized one. Efficiency relating to the size of the engine and the amount of psi you are targeting.

I'll do some more research and let you guys know.
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