WebJan 5, 2013 · 21,014 Posts. #6 · Jan 4, 2013. 4X was used on 400 and 455 Pontiac engines. Fortunately, Pontiac engines are not overly sensitive to lower than "normal" compression ratio. Pontiac production rods are mostly either just OK (cast iron, need ARP bolts) or real pos (forged production rods used in 1959-'62). WebDetails. The Edelbrock #60599 Performer RPM cylinder head is designed for outstanding performance gains in 1962-79 389-455 c.i.d. Pontiac engines. They are patterned after the 1969-70 Ram Air IV Pontiac cylinder head. The Edelbrock #60599 Performer RPM head with the 72cc combustion chamber are for higher compression engines.
Casting #46 heads or #6x? - PY Online Forums - Bringing the Pontiac …
WebPontiac factory cast iron heads came with different styles of sealing such as valve stem o-rings and positive l. Welcome Guest My Account Order Status Wishlist (866)762-7527. ... Pontiac Heads; Pontiac Engine Torque Specs; … WebBP ports more Pontiac cylinder heads than anyone in the world. ... Pontiac Engine Torque Specs; Pontiac Cars (Body Types) Pontiac Engine Information; Instruction Sheets; … campsites great langdale
4X Racing Heads - Tech Articles - High Performance Pontiac …
WebSep 24, 2024 · After consulting with the Pontiac faithful online, Steve learned that the 350's original 6X-4 heads would work perfectly on the 455. Pontiac used these heads in the mid-'70s, and unlike most earlier 350 heads, these utilize the same 2.11/1.66-inch valves as the large-displacement Pontiac engines, while using a combustion chamber that, while good … WebPorts have a thick roof, wall, and gasket material areas for performance port work. Exhaust port is standard Pontiac D-port configuration. Utilizes standard pushrod location for 5/16″ pushrods. Stock ports flow of … WebMar 13, 2014 · However, Pontiac made two different 6X heads in '77. Both have the 2.11/1.66 valves but different combustion chambers. The 6X-8 head was on the 180HP 400s with a 7.6 compression ratio. The 6X-4 heads were on the 200HP 400s with a 8.0 compression ratio. Now to complicate things a little more, the 6X-4/6S head was also … campsites hassocks