Enlarging rear boost port

[Ollies930]

After looking at CPI cylinders and T-Rex cylinders, it occurred to me that the rear boost ports on stock Banshee cylinders, as well as in Athena, Vito's, RDZ, etc., have relatively narrow boost ports. But in a lot of the ported stuff that I have seen pictures of, nobody seemed to widen these even though there is a lot of room available. On CPI and T-Rex cylinders there are two side by side, which appear a lot wider than the stockish ones when added together. Is there a good reason why not to do this? It seems like an obvious improvement to me to gain intake flow and window open area and there does not seem to be any water jackets or other physical hindrances in the way.

Any thoughts on this based on experience?

[trickedcarbine]

If you look really hard through years of content for some images of actual 100+ hp stock cyls you will see some weird shit. But then also, you will see stockers making similar power without even adding BOYHESON ports or much enlargement of the boost port at all. No v on the intake bridge. My opinion.... Some width can help. But the real gain is how deep you open it up and getting it to flow on the right angle.

[registered user]

i know nothing about the cylinder your working with but if the casting allows, and the ring ends dont interfere, your better off bringing the rear transfers farther around back. because of its steep trajectory angle the boost isnt contributing near as much to cylinder filling as the side transfers. and thus your efforts should be on the side transfers

 

this is the problem with alot of cylinders. the ring ends are in a bad location, rear studs are to far forward, and you end up with alot of dead cylinder wall area that could be put to good use