Hi
Can someone explain what the term "ported" is?
Thanks....

 

Well, there isnt really an extremely easy answer here. In the industrial sense porting tools are used to remove casting flaws, imperfections,etc. When you get into bikes and ATV's, 4-stroke and 2-strokes differ also. Porting on a 4-stroke engine usually involves grinding material away from behind the valve pocket areas and matching the intake and exhaust gasket areas in the head itself for a mild port job to really hogging out material from everywhere while using a flowbench to keep flow increasing instead of decreasing. Sometimes epoxy is used to correct tunnel shapes and also imperfections in casting. Keep in mind those 2 types are not everything and every motor combo is different. Now on the 2-stroke............... The most deceiving engines of all. The head of a 4-stroke is what gets worked on, but in a 2-stroke we are dealing with the cylinder itself (sometimes even grinding the cases and other things). Since a 2-stroke cylinder has holes to feed the intake mixture and let the exhaust exit, it would seem that more is better,right? Not always true. A mild porting of a cylinder would be to clean up any imperfections and any mix matches between the liner an aluminum and keep all areas "free flowing". Now most of the time the term "ported" to most would mean that the port timings of the "holes" (relevation of piston placement to port openings) gets changed to open at a different time to produce the wanted power range. There is no secret formula for any given cylinder. Only by time,experience, and sometimes formulas can a person take a cylinder and make it do what he/she wants. Often it involves changes in carburetion, compression, and other tuning areas to benefit and work as a package.But in the utmost simple sense, porting is cleaning ,shaping, and making it free flowing. Hope this didn't get too confusing and helped,Bubba

 

Excellent explaination. In your most simple explanation would an engine with a freeflow aftermarket exhaust and a Uni air filter be considered to be ported, or would one need to go farther and do internal work. Thanks for the great answer.

Jay

 

Porting is done internally. A filter and pipe has nothing to do with being ported.