Profiler Sniper X 174XC3503 - Cylinder Head Cast Aluminum Chevy Big Block 355cc 119cc 24 Degree 2.300" x 1.850", CNC Ported, Bare CastingProfiler Sniper X 74XC3503 Cylinder Head Cast Aluminum Chevy Big Block 355cc 119cc 24 Degree 2. 300" x 1. 850", CNC Ported, Bare Casting The Sniper X cylinder head is the latest BBC head offered in the Sniper Series. Designed with the most up to date technology available, this Sniper X head flows over 430cfm on a 355cc runner and over 325cfm on the exhaust! We started with the most sound casting available and then spent months developing the best port