Properly cooling our MX-5 under all conditions is a priority for all of us. While the stock Mazda radiator on the NA or NB (NBFL) is sufficient for normal driving, it may not be enough for spirited driving or track driving. And when the plastic top and bottom get old and brittle, they start forming cracks and that’s a disaster waiting to happen.
What thickness to choose? Is thicker better? Well, core dimensions are just part of the equation – in order to cool the circulating water, you also need air flow through it. And the thicker the core, the harder it is to push/pull air through it. This 50 mm core radiator is for demanding applications in heavily modified cars (boosted to well over 200 HP or for racing in very hot climate). For cars up to 200 HP, we recommend getting our 40 mm radiator, which works better at lower speeds and still provides great cooling capacity for street and track use.
With this aluminium TIG welded performance radiator you not only gain more coolant volume (cooling capacity), but also improved reliability, better heat dissipation and higher efficiency. It features a two row 50 mm thick brazed core and comes with a 1.1 bar pressure cap to increase the boiling point by a notch. A sturdy metal drain plug makes your coolant change easy. Aluminium construction also removes the risk of breaking or cracking of the plastic radiator parts, which is a common problem on stock radiators.
The radiator is a direct replacement with no mods needed. Radiator fits cars with manual transmission only. You can use the original cooling fans, or get our dual fan shroud for more cooling power.
The aluminium drain plug has a rubber seal, so it should be tightened by hand only to finger tight.
If you’d like to protect your engine even more by fixing the uneven cooling of the factory setup, check out our legendary coolant reroute kit as well.