This very simple system scavenges very well and works well with lower horsepower restricted (near stock) engines. These systems use either a Cup style exit boom tube or an ovalized piece of 3 ½” tubing for the outlet pipe. NOTE: The oval outlet tube system is legal in the NASCAR Late Model Stock Series. The boom tube system, as show in the photo, is not legal in the NASCAR late model stock series, but is permitted in many other series. Check your rules before ordering. Please specify if you are running in the NASCAR Late Model Stock Series, to get the proper system.