This head is designed for large bore (4.125") strokers 
or boosted applications.It uses 2.100 and 1.600 stainless 
valves with 45* valve seats.Combustion chamber finishes
at 69cc or 75cc. Assembled with Ferrea 1000 series competition 
valves, Isky 9385 springs (250#seat/600#open), titanium retainers and 10*
locks. 7/16 studs and guideplates included.