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Old 02-07-2018, 10:27 PM   #14
Burnt Sierra Madre
Join Date: Jan 2009
Location: Fort Joe Smith, Klendathu

Originally Posted by bobxyz View Post
A better description would be: A more efficient turbo producing the same PSI (1bar) is actually flowing a larger mass of air.

Power is mainly proportional to mass of air in the cylinder. Higher temperature air is less dense (e.g. hot air balloon) and has less mass. A lower efficiency turbo will heat the air more, while a higher efficiency turbo (at a given boost point) heats the air less. Less heat means denser air, means more power.

No matter what, compressing air increases the temperature, more so with an inefficient turbo. Hence improving the intercooler reduces the air temperature. Lower temperature air means denser, means more mass, means more power.

At 1bar, a 15g is more efficient than a 13c - the rise in boosted air temp at 1bar with a 15g will be less than a 13c. Thus lower temp 15g air means denser air, means more mass, means more power, and needs more fuel at full boost. The MAF - Mass Air Flow meter measure air mass, not CFM (it has temperature compensation built in) and will automatically adjust the fuel flow to match if the injectors can keep up.
got it
ok, so answer isnt cfm, its T

same psi, same volume, lower T
more air mass, needs more fuel.
comparing cfm is just crappy proxy for temp

i think your explanation is best, no pump pumps more air into a closed chamber once it is at max psi
Originally Posted by lummert View Post
Dammit, Lummert.
Originally Posted by Jesse8931 View Post
Well keep us updated on how your dumbass plan goes.

Last edited by apachechef; 02-07-2018 at 10:50 PM..
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