KevinK2

Yes, more flow from turbos, but not higher pressure pre IC.

Assume on a mustang dyno, putting max wot power out at 4000 rpm, with dyno adjusting resistance to hold speed. Also assume boost regulated to 10 psi in manifold, and no drop across the IC, so 10 psi out the turbo.

case 1

run with IC face coverd, so no charge cooling. Turbo will be reving at say 50,000 rpm and flowing 250F air into manifold and then engine at say 300 cfm.

case 2

use IC to cool charge to 120F. Still have 300 cfm into engine, based on 4K rpm and 10 psi in the manifold. But cooler charge air means more mass flow into the engine and more hp ... say 10% more.

-------> the turbo will supply 10% more mass flow at the same 10 psi. It does this by shifting to the right on it's compressor map at 10 psi boost. This shift will increase flow by:
a) higher efficiency and slightly higher wheel speed, or
b) lower efficiency and much higher wheel speed.

Depends on where you were on the map with case 1.

mad_7tist

ok but the intercooler piping to the intercooler does not change. so if the tubo puts out more air. then the pressure must increase or the temp must go down pre ic to compensate.

300 cfm flowing through the pipe at say 200f will = 10psi (numbers are for kicks)

so if the temp drops to 100f the psi will drop x-amount

if what you are getting at is that most tubos will supply the extra cfm to make up for the loss with little prob i will take your word for it i am just talking to make sure my picture is ok.

KevinK2

Study a compressor map, or better get max boost by corky bell. For my case 2, the temperature can rise or drop at the higher flow rate, at a steady 10 psi.

There is no pressure drop due to temp drop to worry about.

IF ... you had a belt driven Eaton Supercharger for my case 1, then case 2 would likely drop the system pressure, before and aft the IC the same, as the IC now does some of the densification that the SC was doing. Same mass flow, but cooler, lower pressure, and less knock.

seventhgear

maybe this will help someone answer ur question.... the intercooler is off of an Isuzu NPR truck and is the smallest of the 3 different sizes that come on those trucks... is your idle any different? well i think it may be the intercooler also bro...