All Koyorad Racing radiators with welded-on billet filler necks will use Part # SK-C13 (Red Label) Deep plunger style cap. SK-C13 is a common radiator cap style that will is compatible with many Japanese vehicles.

50/50 coolant antifreeze mix is mandatory. Use OEM manufacturer’s recommended coolant.

Prior to installation, a complete cooling system flush (including heater core flush) is mandatory in order to eliminate any old coolant, contaminants, mineral deposits, and previous additives. Dex-Cool is not to be used with Koyorad all-aluminum radiators.

Follow vehicle factory service manual for proper filling of the cooling system after a Koyorad all-aluminim radiator has been installed. Reference vehicle owner’s manual for coolant capacity, then 1 additional gallon on-hand to top-off.

All-aluminum Koyorad radiators will accept genuine replacement drain plugs (include rubber gasket), Part# PI1186. This can be purchased from any Koyorad dealer.

N-FLO Dual Pass Technology features welded internal partitions that force coolant to circulate through the radiator core twice, increasing coolant dwell time and heat dissipation. The result is improved cooling efficiency and greater thermal control for high-performance applications. NFLO radiators can be identified by the “N” following the Koyorad part number.