Works on the following Holley/Weiand Big Block Chevrolet intakes:

• 300-561 for Oval Port Heads with 4150 Square Bore Carburetor Flange
• 300-562 for Oval Port Heads with 4500 Dominator Carburetor Flange
• 300-563 for Rectangular Port Heads with 4150 Square Bore Carburetor Flange
• 300-564 for Rectangular Port Heads with 4500 Dominator Carburetor Flange

Weiand has taken this technology and designed a new line of Track Warrior manifolds perfect for aggressive street machines and Comp/Super class big block power plants. This fuel rail kit is designed for those EFI manifolds. Computer engineered and dyno proven to produce more horsepower and torque as a result of superior cylinder to cylinder distribution gives this piece the edge over the competition and ensures safe, consistent air/fuel ratios for your engine. Permanent mold castings provide weight savings of 10 to 20% over traditional sand cast pieces while maintaining uniform wall thickness for porting.