• Direct fit for 2006-2015 Mazda NC Miata MX-5
• 34mm core is 112% thicker than stock
• 114% increase in core volume
• 51% increase in fluid capacity
• 92% increase in fin surface area
• All-aluminum construction with durable, TIG-welded end tanks
• Includes Mishimoto Magnetic Oil Drain Plug with high-quality dowty seal
• Mishimoto Lifetime Warranty

PURCHASE INCLUDES

(1) Mishimoto Performance Aluminum Radiator
(1) Magnetic Drain Plug
Mounting Hardware
Mishimoto Lifetime Warranty

PRODUCT SPECS

Mazda designed the NC Miata for the utilization of all 170 equipped horsepower. This budget sports car’s idea is to show the automotive world that you don’t need 1,000 horsepower and enough torque to shift the earth off its axis to have fun behind the wheel. Let’s be honest, in most situations, you can really only use a fraction of that power unless you’re at the track or drag strip. On the other hand, you can use all the Miata’s available power and still have your driver’s license at the end of the day.

However, a car designed to live at the limit will be more prone to cooling issues. Our new radiator design is tailor-made to ensure that your NC can keep its cool, even when it’s running at the limit.

When we last left off, our design was just an outline. We created a prototype to triple-check the fitment of our bigger core and revised end tanks before kicking off production. Well, production is wrapping up, and our final design is in the house.

We kept our promises from the last post regarding the production unit, starting with the complete aluminum construction. All plastic is gone, and the end tanks are now fully aluminum and TIG-welded to the core for maximum durability on the street or track.

The improvements don’t stop at the end tanks, and the core also received a much-needed overhaul. Our new core retains the lightweight tube-and-fin construction but is redesigned from the ground up for improved heat management. For starters, it’s bigger. Specifically, we were able to double the core thickness, expanding from 16mm to 34mm. This core expansion equates to a 114% bump in core volume coupled with a 51% increase in fluid capacity.

To further improve the Miata’s cooling power, our engineering team also revised the fin design to pack even more fins into the radiator’s core. The updated core even squeezes in more rows resulting in a 92% external fin surface increase for improved heat dissipation. We also included our specialized louvered fin design, which forces the fresh air through the core diagonally, providing more time for heat transfer and more cooling power.

The essence of the Miata is that big fun comes in a small package. Every horsepower and foot-pound of torque is usable daily and sure to make your face match the smiley NC fascia. Still, bigger is better when it comes to cooling, even in the Miata. With a car designed to “celebrate driving,” as the Mazda motto goes, a little extra security in the cooling department is never a bad thing. Make sure that you get yours today!

It’s true what they say, failing to plan is planning to fail, especially when it comes to pushing your vehicle to the limits. As we covered in the first post, the MX-5 Miata is designed for being pushed to the ragged edge, and driving so close to a vehicle’s limit requires some preparation. Surely, Mazda put some extensive engineering behind the Miata’s cooling system, but even still, it can have some trouble keeping up once you put the hammer down. When it comes to our radiator design, we plan to improve the NC’s endurance.

Our plan is straightforward and parallels the sports car formula’s simplicity that makes the Miata so successful. We start by ditching the plastic end tanks. This means of end tank construction is ideal for huge production runs because of Mazda’s ability to churn out thousands while reducing production costs, but there are drawbacks. Plastic wears out over time, especially when there’s a constant and extreme fluctuation in temperature. Over the years, this can cause cracks and leaks, which, it’s a known fact that coolant works best when it stays in the system.

We plan to swap the plastic end tanks for a full aluminum construction, TIG-welded to the core. This construction is much more robust and better suited for constant heating cycles. Also, the aluminum end tanks help create a more rigid radiator that can resist chassis flex. We’re opting to retain the factory locations for the inlet and outlet, and mounting fixtures for ease of installation.

The end tanks are only part of the equation, and the factory core was in desperate need of an overhaul. Given the tight space in the front of the Miata, our engineer, Dan, wasn’t able to make many adjustments to the height or length to the planned design, so he focused on other aspects to improve cooling. Core thickness became the main focus in that case, and Dan is planning on adding about 18mm to the width of our new design. With the extra thickness, that means plenty of space to add a second row of internal coolant passages for a more efficient radiator.

When it comes to the fins, the plan is also reasonably simple. We’re already planning on retaining the same louvered design to add even more heat dissipation power to the new core. Other than that, the plan is to pack as many in the same space as we can. Dan is making precision adjustments to the fin design that would allow for some serious fin cramming. Coupled with the increased core volume, we anticipate plenty of additional cooling power for the Miata.

So far, our plan has only made it as far as our fitment prototype to ensure proper fitment. With the design finalized, our first run of production samples are on the way to our R&D facility, so make sure that you stick around for the first look at our new NC Miata radiator.

When it comes to sports cars, sometimes the real joy doesn’t come from a monstrous motor with oodles of power, but rather something small and nimble. A car that lets you utilize every horsepower and push it to the absolute limit. The NC MX-5 Miata defines that category. Sure, it might only have 170 hp, but you can use every single one, and effectively too. Thanks to its double-wishbone front and multilink rear suspension setups, the NC is more than capable of transporting you to the ragged edge with the wind in your hair and a grin on your face matching the Miata’s front fascia.

But, there’s always a downside, and in the case of the NC Miata, it comes as heat. Like any car, the Miata was designed to be driven. The spirit of the Miata lends itself to being driven hard, which makes it even more likely to experience high temperatures. Luckily, we here at Mishimoto are hard at work devising a better means of coolant temperature regulation.

The NC Miata follows the same design language as many other front-engine sports cars: simple, smooth lines with only one opening on the front of the car that supplies fresh air to the engine bay and cooling stack. The engineers at Mazda wanted to make sure the Miata’s radiator soaks up as much of this air as possible, so they angled it toward the opening, similar to the radiators on the C6 and C7 Corvette. Mazda’s cooling strategy didn’t stop there, so we pulled the stock radiator to get a closer look.

Once removed from the vehicle, we saw that the Miata’s radiator’s construction follows the same theme that we typically see in OEM radiator production. The radiator is made up of a pair of plastic-injected end tanks crimped onto a lightweight aluminum core. The stock core features louvered fins, which force the air through diagonally, theoretically expanding the core’s thickness and improving the cooling power. But, while the louvered fins help improve the radiator’s efficiency, this core needs all the help it can get. The core of the radiator measures in at a measly 16mm, or 0.6″. That thin core may adequately cool the 2.0 MZR engine during normal driving, but the cooling system could reach its limit much sooner during a hot day on the track, or even a long stretch of back roads.

Half the fun of owning a car like the NC Miata is that you can push it to the absolute limit, and it will gladly live there, but for how long? Given the flimsy stock radiator, the chances of the MX-5 pressing on after a few thrashings are slim. So if you bought your NC to live at the limit, make sure you stay tuned for the first look at our plans to strengthen the Miata’s radiator.

Install Guide: