McCarthy

As per the title really. Whats peoples veiws on totally round peripheral ports compared to rectanguler ones?

trochoid

iTrader: (6)

I've never worked with them, but from enigeering point of view, they are easier for the DIY builder to make. A round hole will flow less total volume than a rectangular but once the the hole has been drilled, porting a round hole to a rectangular one isn't hard, depending on how the sleeve is installed. For high rpm engines, rounding the top/closing part of the port will put less stress on the apex seals.