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SuperMiata SPMQmax
SuperMiata Qmax Cooling kit
Price: $598.00
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Detailed Description

Qmax Cooling Kit

Supermiata Crossflow Radiator & Supermiata Qmax Coolant Reroute
Miata Roadster Eunos MX5 89-05

This kit is the cornerstone of getting a track Miata to stay cool in hot weather


Why crossflow?
The Crossflow utilizes a side to side coolant flow pattern. The OEM and most aftermarket radiators have a downflow top and bottom tank configuration. The primary advantage of a crossflow is the longer transverse coolant path allows more time to shed heat.  Placing the filler on the low pressure side also prevents the cap from releasing pressure prematurely as it can in traditional top/bottm tank designs. The core also features carefully optimzed fin density and thickness to allow the maximum cooling in the most compact and lightweight radiator. This lightweight 31mm core will cool more efficiently than the Koyo 55mm we also offer.

Radiator features
Starting with a clean sheet of paper, we were able to include the features of the best radiators on the market and add a few of our own.

  • Two drain plugs. Each drain plug is a common 10x1.5 bolt with a simple o-ring. Lose a plug? 10 minutes at your local auto parts or hardware store and you are back in business.
  • High flow fill neck. Nothing more anoying that bleeding a cooling system that has a tiny filler neck that requires a funnel and slo-mo filling. 
  • High pressure 1.4 bar (20psi), high temp cap. The standard cap with our radiator will allow your system to operate at 25% higher system pressure. That raises the boiling point even further. The seal is high temp silicone, not rubber that will crack and leak.
  • B tube core. The B tube is actually two tubes in one. The B tube has a septum, or divider that runs down the center of each tube. This increases the surface area and help to equalize the wall pressures inside the tube to further optimizing cooling efficiency. Our core is one continuous tube, not two cores sandwiched like you might see in other large capacity cores. This means maximum surface area with minimal external size/weight.
  • High fin density. Our core is 19.5 fpi, or fins per inch. Our testing has shown that 18-21 fpi is the sweet spot given the airflow, temp deltas and water pressure of  Miata system.
  • Compact 6.5mm fin height increase coolant to core contact area
  • Convertible. Our radiator will fit any year 89-05 MX5 Miata with included hardware. 
  • Light weight design. 7.8 lbs, the lightest aftermarket aluminum radiator available

Why reroute?
The B series engine in the Miata was designed for a fwd car. As with all inline 4 cyl engines, coolant entered one one end of the head and exited the other end in the fwd application. This simple path is the most efficient way to extract heat from the head. Mazda turned the engine 90° and tucked it up against the firewall in the Miata. This meant moving the coolant exit to the front, the same end of the head as the inlet. This poor flow path is the primary cause for overheating which is so common in the 90-05 MX5. Our reroute has a carefully engineered low profile adapter for the back of the head to retain the original front to back coolant path. Just this one modification will significantly reduce coolant temps. Even a bone stock Miata will run a bit hot, and the stock ECU will reduce ignition timing which hurts power and fuel economy.

The Qmax Reroute Features

  • Internally machined to maximize coolant velocity which is key to improving cooling efficiency.
  • Retain the use of your EGR pipe for emissions or CEL.
  • The OEM coolant temp sensor location is retained so the wiring harness does not need to be modified.
  • Spare 1/8 NPT ports are provided for aftermarket coolant temp or coolant pressure sensors.
  • All important hardware is stainless steel to increase service life.
  • High flow Stant Superstat is utilized to increase coolant velocity.
  • Simple sealed adapter housing elminates gaskets and finicky, leak prone threaded fittings.
  • Convenient bleed port allows system bleeding with car level if you have COPS ignition.
  • No remote thermostat housing for easy fitment and improved reliability.

To learn more about your 90-05 Miata cooling system and how to improve efficieny, visit this forum article we wrote:  Miata Cooling System Thread.

Drain plugs and radiator cap included

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