whats the valve size in pyramid power pack head ?

[james fuller]

are these heads (1965) with the pyramid marking 194 ,150 ?

[Mike P]

Nope the intakes are smaller, 1.72s and the exhausts should be 1.5 if memory serves correctly.

[james fuller]

ok what about the stock head compared to the power pack ? thanks!

[southerner]

ok what about the stock head compared to the power pack ? thanks!

Do you mean the same year stock heads ?

[james fuller]

any 60's 283 stock head. was the exhaust smaller?

[southerner]

There were 2 standard size valves in the sixtys. The exhaust on all heads was smaller than the intakes. But back to your 283 heads the standard size right through was 1.5 inch exhaust, what mainly changed on the heads was intake volume and profile, and chamber shape, (slightly). They were still all closed chamber and the chamber volumns changed as well.

[james fuller]

thanks southerner i understand it now ! p.s. i married a aussie girl from perth i met while in the navy in 1967 !! still am !!!

[Bob W]

The 520 casting heads used on 283s had 1.72 intakes and 1.50 exhausts but the same casting was used for the 250 hp 327 engine and then they had 1.94 intake valves installed.

Bob