PRO1 ALUMINUM SMALL BLOCK CHEVY CYL

The Dart Pro 1 chamber features improved fuel distribution, optimized spark plug location, and redesigned intake/exhaust faces and ports for greater control over flow, heat, and combustion. These heads are cast from virgin 355-T61 aerospace alloy for superior strength. They retain standard valve angle and spacing for compatibility with off-the-shelf pistons and valvetrain components. The heart-shaped chambers improve combustion efficiency and fit most standard pistons. Multi-angle intake seats and radiused exhaust seats significantly increase airflow. Hardened exhaust seats are compatible with unleaded gasoline. Manganese bronze intake valve guides and phosphorous bronze exhaust valve guides extend cylinder head life. They offer a choice of angled or straight spark plugs to clear manifolds and headers, with spark plug holes machined for gasketed 3/4\" reach plugs. A dual exhaust bolt pattern spot is provided for easy header fitment. These cylinder heads are sold individually. They are designed for serious street performance, modified oval track, and bracket racing applications, suitable for mid-range to 7,000 RPM and best for 400+ cubic inch engines. The 215cc Platinum series heads favor peak power over low-end flexibility.