Stock port size, 6~versus~4
 

Which engine has bigger porting stock for stock, a 6port or a 4port(s4 or s5)?

6 port has longer duration.
Both connected to their LIM's, my flowbench says the 4 port flows more.
My power experiences with similarly built 4 port engines vs. N/A engines gives similar results.

I thought that 4 port engines only flow more if they are ported?

That was my understanding aswell, hence why I posted this thread. I'd love to get some solid info for this question.