Oval port BB heads???????

[VintageMusclecar]

A brief gloss-over on oval port heads, FWIW;

All oval ports from `65 through `70 were of the closed chamber variety and all were factory equipped with 2.06 1.72 valves. There were minor variations in the combustion chambers over the years, with the later year heads having a relief cast in by the plug side of the chamber (if memory serves correct, the 290 and 215 heads have this relief). There were other minor differences in the castings over the years as well.

From 1971 through 1972, the oval port heads were of a semi-open chamber variety with a large relief cast into the chamber on the quench side by the exhaust valve. These heads actually perform pretty well on the street, although many enthusiasts tend to overlook them.

Starting in 1973, oval ports were cast with a true open-chamber design, i.e. the 049 and 781 heads, which are quite popular with countless performance enthusiasts and engine builders.

Hope that helps.
Eric

[Verne_Frantz]

Thanks for the education guys. I have a loner 702 that's not doing me any good except taking up room on my shelf.... Sure seems odd Chevy would have 2 castings that were so similar. I have to wonder if there was something else to it.