Exhaust

SS_Firehawk

Not the easiest thing to describe but... Essentially your exhaust has natural pulses as cylinders go through the combustion process that travel through your exhaust. When it hits the merge collector of your header (exhaust manifold), it creates a vacuum, sucking out the old residual fumes still in your combustion chamber. You get an added bonus of Y pipes, H pipes, and X pipes benefiting scavenging as well. When your exhaust pipes are small, your exhaust velocity is high, helping scavenging at low rpm, but suffering from back pressure at high rpm. For naturally aspirated Z's, the magic number tends to be a 2.5" Y, H, or X pipe, dumping into either a 3" single or 2.5" dual mid pipes and out the muffler.

There you go, Scavenging 101.

__________________