What is exhaust scavenging?(vacuum behind exhaust pulses)
Exhaust scavenging is the ability of the exhaust to create high velocity situtation where while overlap is ocurring the combustion chamber can be completely emptied and actually filled with fresh air from the intake. This can only happen while the piston is at or near TDC and the intake and exhaust valves are open.
I googled it and above is one of the hits I got.
Don
