i know if you have a fire hose and choke it down to a garden hose it can only flow as good as a garden hose. it can only flow as good as its smallest part. i'm confused about the exhaust systems, with a 3" down pipe and mandrel bent 3" system without a cat and with a high flow muffler would be as good as it gets ( with a muffler) but then i look at the output from the turbo itself, reguardless of the swingvalve size, i think its well under 3" so what am i missing? same as the exhaust manifold side i understand longer tubes is a good thing. but beyond that if you add the size of the ports on the head, and compare it to the size of the turbo inlet it don't seem that much improvement can be made other than longer tubes, am i right? i'm guessing i'm not but i don't understand why.