PRO1 CNC ALUMINUM BBC 24

Dart Pro 1 CNC Ported Big Block Heads. Professional quality competition cylinder heads. Airflow technology developed in championship-winning Pro Stock engine program. Every intake port, exhaust runner, valve bowl, and combustion chamber is 100% CNC machined on dedicated Pro 1 castings using five-axis, computer-controlled machining centers for compound curves and complex shapes. Features premium alloy cast from virgin 355-T61 aerospace alloy for superior strength and integrity. Bolt-on compatibility, 2-degree rolled valve angle, and standard spacing accommodate all stock accessories. Available with 335cc and 355cc intake ports to match runner volume to engine's displacement and RPM range. Heart-shaped 121cc chambers improve combustion efficiency. CNC machining ensures every chamber has the same volume for equal compression. Raised spark plug location improves flame travel for quicker, more complete burn, producing more power. Multi-angle intake seats and radiused exhaust seats dramatically increase airflow. Hardened exhaust seats are compatible with unleaded gasoline. Exhaust ports raised .300" to improve flow (requires 1" longer head bolts next to exhaust ports). Spark plug holes machined for gasketed 3/4" reach plugs. Manganese bronze valve guides extend cylinder head life and reduce stem wear.