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Old 05-02-2016, 12:47 PM   #28 (permalink)
cofo11
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Quote:
Originally Posted by Chuck33079 View Post
You have to take flow into consideration. 10psi out of a large turbo is a lot more cfm than the same psi out of a small turbo.
No, it is not. A larger turbo has the potential to flow more cfm and will be using a smaller percentage of its flow potential at the same PSI than a smaller turbo would, but 10 PSI is 10 PSI. If the downstream tubes are larger it would take more volume of air to create 10 lbs of pressure but you would still only have 10 PSI.

PSI is a function of pressure, not volume. The reason it is called FORCED Induction is that you are forcing air into the motor at a rate exceeding what the motor pulls on its own. You can have an unlimited volume (vented to the atmosphere right off of the manifold) of air available and (assuming a correctly designed intake ie no flow restriction) will still only pull in what the motor pulls through its intakes. When you add FI you are utilizing the pressure (PSI bar etc) the device creates to force more air into the motor. Thus 10PSI of air entering the same intake manifold will always be the same 10 PSI of air no matter the size of the pump. The only way to get more air into the motor is to increase the pounds per inch.


What you are describing with the "more cfm" of the larger compressor is pushing more volume into the same space thus raising the PSI of the system.

Last edited by cofo11; 05-02-2016 at 12:51 PM.
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