AFR emissions legal (CARB #D-250-4) 210cc LSx heads are the cost effective performance choice over re-worked factory heads. They feature 100% CNC ported intake, exhaust and chambers, A356 aluminum castings, Titanium retainers and high quality components throughout. Recommended for street, towing, or street/strip engines with displacements up to 383 cubic inches, operating up to 6300 RPM. Requires minimum 3.900 bore for intake valve clearance. AFR heads are available bare (without parts), call our tech line for details.