Buick 401 Nailhead Pistons

Replacement cast aluminum 4.1875″ bore piston set for ’59-’66 Buick 401 Nailhead.
Cast from high silicon A-332 aluminum alloy Machined on modern CNC machinery Precision balanced & weight-matched sets Balanced to within 8 grams from the lightest to the heaviest piston The 401 rings are a cast top, and a cast second ring.