Radiator Cap with Cover

The ALLSTAR PERFORMANCE radiator cap with cover (SKU ALL 30139) is an essential cooling system component designed for vehicles using standard-size radiator necks. This 16 lb pressure-rated cap maintains optimal coolant circulation and prevents system overpressurization, making it a critical safety and reliability upgrade for street rods, classic cars, and performance vehicles. The included cover protects against debris and UV exposure while adding a polished aluminum aesthetic to any engine bay.

Constructed from polished aluminum with a hexagon design, this radiator cap delivers both form and function. The 16 lb pressure rating allows the cooling system to operate at elevated temperatures before venting excess pressure, which raises the boiling point of coolant and improves heat transfer efficiency. The hexagon shape provides secure grip and ease of removal, while the polished finish resists corrosion and complements traditional hot rod styling. The integrated cover shields the cap from road spray and contamination, extending service life and maintaining a clean appearance.

This radiator cap is ideal for builders and restorers working with standard radiator neck configurations who demand quality and visual appeal alongside function. Installation is straightforward—simply replace the existing cap on any compatible radiator equipped with a standard-size neck opening. The polished aluminum construction and included cover make this a popular choice for show vehicles and performance builds where engine compartment aesthetics matter as much as reliability.