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hobieboy hobieboy is offline
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Join Date: May 2002
Location: Up North
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Originally Posted by DW SD View Post
If you look at the ideal gas law this might explain the issue. I think it is about heat added through the turbocharger.
Originally Posted by DW SD View Post
conclusion: if absolute temperature were higher then HP would drop. Conversely if pressure increases, temp is fixed, HP goes up.

A drop in temperature of 20 F degrees to 150 F from 170 F is about 11 degrees on the absolute scale. 338.5 K from 349.6 K, which equates to 3.0% more molecules of air to burn.
That is exactly what prompted my question... according to my datalog, my intake air temp, taken just before the butterfly, is "constant" regardless of boost (or no boost).

My turbo can hold the boost pressure I want to run (~= 1bar) at "most" RPM range & gears. So, why/how could a bigger turbo increase hp?

I guess GJF is starting to convince me that pressure <> volume hence same pressure, bigger turbo puts out more volume. But, what is the make up of the volume that would create pressure/boost? In vacuum or high altitude, it will take more volume of air to make same pressure because of lower air density, no?

So, if we are talking about same pressure, then volume is same UNLESS density is different. But, density should be same if air temp is the same (assuming same altitude)? If this is true, are we not back to: same pressure from 2 turbos = same volume = same hp?

I am confused....
87 930 K27HFS/B&B/Twin-Plug... Megasquirted
Old 07-15-2008, 06:10 PM
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