GMC Truck, 1963-66 L6 230 Radiator

Based on 60's style core with 1/2" tubes on 9/16" centers; the standard automotive core units are drop-in, stock replacements. Made from all new material they offer the highest quality for your stock application.

Copper 80's style core with 1/2" tubes on 3/8" centers. Increased cooling efficiency without modifications to car. 4 row High Efficiency offers more cooling efficiency than aluminum cores due to tubes on 3/8" centers. Copper/brass construction to ensure dependability.

By re-routing the coolant through the core three times the coolant travels farther in the temperature reducing air-flow and the additional time spent dropping temperature results in amazing heat transfer rates. Copper/brass construction to ensure dependability. (note: Tripleflow option requires that inlet and outlet be on opposite sides and must use auxiliary tranny cooler for automatic transmission vehicles)

Extreme style copper core with 1/2" tubes on 5/16" centers. Offers 40% more heat transfer points. The most efficient core on the market when combined with increased air-flow and our Tripleflow option (note: In almost all cases, we will not sell the Optima core without the Tripleflow option. Our Tripleflow option requires that inlet and outlet be on opposite sides and must use auxillary tranny cooler for automatic transmission vehicles).