Designed for non-emissions 289, 302, and 351-Windsor Ford engines, these direct bolt-on heads deliver maximum performance in the 1500-6500 rpm range for all high performance street applications and our Performer RPM Power Package. Performer RPM head #350-6026 has high-flow 2.02'' intake valves which require aftermarket pistons notched for valve clearance. Will not accept rail rockers.Note: Aftermarket 286/302 heads including Brodix, Edelbrock, Ford Motorsport and World Products with 1/2'' bolt hole diameters (block is 7/16'' bolt hole), except 397-M-6049-P303 (''P'' style head). Require 350-9680 inserts with 350-8552 head bolt or 350-9680 insert with 070-154-3601. If head studs are desired use 070-154-4005 (includes inserts).
Tech Tip: To gain more spark plug clearance, Edelbrock recommends using Champion RC Series plugs such as the RC12YC (P/N 192-49776). They are 0.230'' shorter than a conventional spark plug and have a 5/8'' hex for easier access.