I am going to go out on a limb and I am far from an engineer but if the combustion engine(which is essentially is a vacuum mixed with air, fuel, and fire/spark)doesn't have proper flow through the entire intake and exhaust system(cat back, turbo back, down pipe, etc. you know what I mean)then it's going to make less power despite tons of boost. Like for example one of my favorite engines b/c though its(head 15 degree 12v)not the best flowing engine, if you do a proper P&P, BVH and Cams, you can run 12lbs. of boost on the engine and make anywhere from a conservative 30+whp to 60+whp on a 12v VR6 that had the same turbo or S/C set up but didn't have the higher flow. However do people who d boost applications ever go this extra mile with head work and cams? Usually not but when you're from the 12v VR6 15degree angle head family most try to do at the very least a P&P with cams.(Expensive as hell b/c you literally have to look at head work in an entirely new way)Isn't this why people port Super Chargers so they can get more air flow? Plus if you can't keep the proper cooler to the engine you're not going to make as much power.
When you talk about the air going into the engine do you speak of its temp as well? I am guessing that in a N/A Engine the temp of the air isn't as big of a factor(still a big factor)as a turbo/supercharger application. So heat obviously has a factor on air density hence why people use intercoolers but you can have too big of an intercooler so it's important to fit the right intercooler to the right turbo?
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