This manifold has flanges specifically designed for Dart 18/16 Degree SBC Heads. Single-plane, high-rise intakes designed to produce maximum power at higher rpm. Carburetor pad for 4150 carbs. Extended runner dividers equalize port length and are radiused to equalize cylinder-to cylinder fuel distribution. Optimized runner cross-sectional area maintains high mixture velocity for maximum torque. Angled runners turn the airfuel mixture smoothly from carburetor to ports. Dual distributor hold-downs simplify timing adjustments. Manifold flanges are scalloped to clear center water outlets, and bosses for rear coolant lines are provided. Raised water cross-over and air gap insulate the intake charge from engine heat.