Cant completely agree on the port size theory.Doesnt take into account chamber shape and efficiency which affects flame travel.True a smaller port will have better velocity.But a swirl port creates a better burn=more efficient.Thats part of the deal with some smaller ports.
The confuesing thing about swirl ports is that they are misunderstood, if you would use high flow in place of swirl port you would better understand the meaning behind the words. (not to say that you don't understand you more than likely do) but It's not the chamber that creates the swirl, it's how the port is shaped. The chambers were designed for better emissions which aided in better efficientcy. The actual area is similar in the chambers from the early to late engines cc wise. The best chamber that they have come up with so far was in the W-8 and W-9 heads and the P-5 and P-7 heads. The only engines that I've seen this on, on the street from Mopar is on the 3.3 and the 3.5 caravan engines that have this chamber shape.
If they would use this chamber shape in the commandos and the W-2 they would really have something that would kick some serious butt. But unfortunately they only use it in the W8/9 and the P-5/7 series which doesn't lend itself to our use now. Maybe they'll wakeup, I've talked to head manufactures and until they would get a large order they won't even consider it.
Yup I do understand about swirl ports and "shaped" air fuel charges.The chamber shape and quench promotes burn.Sorry if I sounded confused.My wife accuses me of that all the time,lol..
I am starting to think I may be better off just shaving the heads down rather than trying to find an inexpensive piston to bring comp up.
Was thinkin that if the 318 needs an overbore why not try to kill two birds with one stone?Get the right oversize piston that will bring comp up as well..Seemed to make sence to me.