325cc 2.250 x 1.880 1.625 Dual Spring The trend-setting Pro1 heads have been completely redesigned inside and out! A new highly efficient chamber with improved fuel distribution, spark plugs located as high and and as close to the center of the chamber as possible and five-angle intake seats to shear the liquid fuel and air as it enters the chamber are the product of wet-flow research. Additional features which really set these heads apart include a new exhaust port design, new exhaust face and fully machined end pads. Inspired by our championship-winning Pro Stock designs, the PRO 1’s race-proven features include rolled valve angles, extra-long intake valves and raised exhaust ports - yet the PRO 1 can be used with off-the-shelf pistons, valvetrain components, and intake manifolds. |