Home >> Cylinder Heads >> Dart >> PRO 1 Aluminum Dart Heads- "PRO 1" Aluminum PRO 1 aluminum big block cylinder heads deliver "out-of-the-box" airflow that beats the competition--at an unbeatable price! Specifically designed for street performance, bracket racing, and Super eliminator engines, PRO 1 heads make Pro Stock airflow technology affordable for every big block owner. Inspired by our championship-winning Pro Stock designs, the PRO 1's race-proven features include roller valve angles, extra-long intake valves, raised exhaust ports, and fast-burn combustion chambers--yet the PRO 1 can be used with off-the-shelf pistons, valvetrain components, and intake manifolds. You get more power for you money with PRO 1! Using advanced manufacturing techniques, we cast the PRO 1's ports with incredible accuracy. This precision casting technology duplicates the contours that were previously available only in hand-ported and CNC machined cylinder heads. PRO 1 big block heads are available with a choice of three different intake port sizes--310cc, 325cc, and 345cc--so you can match the runners to your engine's displacement and rpm range perfectly. Dart's new PRO 1 is your best buy in aluminum cylinder heads! Combustion chambers available with 64cc or 72cc volume to tailor compression ratio to individual requirements. Heart-shaped chambers improve combustion efficiency and fit most standard pistons. Multi-angle intake seats and radiused exhaust seats dramatically increase airflow. Hardened exhaust seats are compatible with unleaded gasoline. Raised exhaust port roof improves flow while retaining standard port location and bolt pattern. Choice of angled or straight spark plugs to clear manifolds and headers. Spark plug holes are machined for gasketed 3/4" reach plugs. Assemblies include: Stainless steel valves, valve springs, retainers, locks, studs, guide plates, and seals  SB Bare Castings  SB Complete Assemblies  BB Bare/Complete Assemblies