Round port heads came on the highest horsepower pontiacs in 1968 1969 and 1971 1974. If the header port is too small the flow would be similiar to whitewater if its too large it would be similiar to water flowing over a.
Techtips Big Block Chevy Cylinder Head Basics
Round port headers on d port heads. These 2125 round port raiv exhaust flanges are cnc cut from 38 thick steel. Arp cylinder head bolt kit round port pontiac v8 pn 190 3601 see more like this mr gasket 5966 exhaust manifold gasket set round port diameter 192 fits. Its not as much of an issue if the header is slightly larger but smaller is terrible. Pontiac authorized mr gasket dealer. I bought the flo master american thunder kit. Designed for all round port heads like the kre high port edelbrock and ram air ii iv and dci tiger head.
Port matching from the head to the header is critical for peak performance. How will this effect my performance. Theyre called round ports because of the round shape of the exhaust ports which is the part of the head that connects to the exhaust manifold or header. Should i off the headers and get square port headers. They will fit and the gasket shows that the shape is pretty close. The d port head looks like a set of ds mirroring each other in other words back to back.
Below is a picture of the edelbrock round port and d port heads side by side. Do they make square port block hugger headers. They are much rarer than pontiacs d port heads because they were produced in limited quantities. This is not a d port head but a round port instead. Great start for those making a set of 2 18 headers for your high port combinations. You have to make a cut in front of the axle tube and add 1 for a little more clearance for travel up.
Round port heads are exotic stuff only used on the highest. Hello guys if your looking for an exhaust system from the headers back with church boys 4 link here ya go. Compare the flow of your exhaust to a river. The first question is the ability to distinguish between the two types of heads. I noticed that the heads were square port and the headers were round port. One would notice that the round port actually looks like a sideways d that is pointing upwards.
The only other major variation in pontiac v 8s is found in the exhaust ports and here you have a choice of round port or d port. I havent noticed any square port block hugger headers in my catalogs.
Gallery of Round Port Headers On D Port Heads
