Another thing related on the smaller port castings, such as a 17. They can't be opened up as much before hitting water, as compared to a 16 dport for instance.
When the Pontiac engineers designed the smaller port heads with smaller valves they just didn't add material and make the castings thicker, thus heavier.
There is a relationship between how thick a casting is and how quickly it will dissipate heat. A major consideration of a head design. Pontiacs are good designs in that area. Not a lot of cracked Pontiac head castings out there.
__________________
1963 Cat SD Clone (old school) streeter
1964 GTO post coupe, tripower, 4speed (build)
1965 GTO 389 tripower, 4 speed, driver
1966 GTO dragcar
1966 GTO Tri power, 4speed, barn find
1966 GTO Ragtop
1969 GTO Judge RA lll, auto
1970 GP SSJ
1970 GTO barn find..TLB…390 horse?….yeh, 390
1973 Grand Safari wagon, 700hp stoplight sleeper
525ci DCI & 609ci LM V head builds
Factory stock oval track car
Last edited by J.C.you; 05-02-2018 at 09:57 AM.
|