Sections that are 12 feet long are not uncommon for round and flat oval. Rectangular ductwork is typically limited to 5-foot lengths. This results in less than half the number of joints in round and ...

We test rectangle versus oval ports on a Chevy big-block and give you the dyno numbers. Only at carcraft.com or the November 2011 issue of Car Craft Magazine.

Oval ports and rectangular port heads. HOT ROD Staff Writer Jul 18, 2012. See All 31 Photos. Two issues back, we subjected a 468-inch big-block Chevy to a variety of different oval-port cylinder ...