replied to the thread Intercooler Comparison (BMW Stock vs. Wagner EVO1 vs. HPF vs. Mosselman)
" Oh no no sorry, I'm too literal sometimes. VE is all about how much air you can cram into/out of the engine. Density of air is one part yes a big part... but if you can increase the velocity, you can get the same amount in per time. There's of course other concerns... but anyway...
What I mean is yes they rate in terms of pressure ratios for the turbine only I think, as exhaust moves past. So pre turbine pressure vs after turbo pressure. In a given restriction (the AR ratios) this should produce x force on the turbine (Hotter gas is good here, more pressure, more energy in general for the turbo to recycle). But technically I think it's still related to a mass flow, mostly since the volume in a steel pipe is constant, if that makes sense.
And then the compressor maps are rated in lbs or cfm vs pressure... so you'd calculate how much airflow (mass flow) your engine sucks, determine its restriction at that number (how much psi it will take to get that flow), and you'll see the compressor efficiency.
I think that's right. But right now my mind is all about head and neck anatomy. "
Today, 05:03 AM