When creating the initial MX-5 Miata design, they adopted an existing B-series engine to drive the vehicle. They repositioned the engine orientation from transverse to longitudinal and shifted the coolant outlet from the rear to the front of the engine, leading to a modification in coolant circulation. With both the coolant inlet and outlet now situated at the front, significantly less coolant reaches the rear of the engine, resulting in reduced heat dissipation from the cylinders in the rear. This alteration is applicable to all models produced from 1989 to 2005, encompassing the first two generations of the car.

Furthermore, this adjustment adversely affected the overall efficiency of the cooling system. Mazda attempted to address this issue by incorporating a larger radiator into the design, but even with this adaptation, the system encounters challenges when subjected to heavy loads, leading to a noticeable increase in temperature for cylinder 4. This temperature disparity can be quantifiably observed.

Mazda is aware of this problem and attempted to address it by replacing the head gasket in the NBFL (MK2.5) models. The new gasket, however, limits the coolant flow to cylinders 1 and 2, directing more coolant towards the rear. Consequently, while the issues are somewhat alleviated with the 2001+ head gaskets, further constraining the overall coolant circulation is not a satisfactory resolution.

A coolant reroute involves relocating the front coolant outlet to the rear, effectively reinstating the original engine configuration.

I recently installed the SkidNation MX-5 Premium Coolant Reroute Kit on my Mazda MX-5, and the results have been impressive. This modification has significantly enhanced the car’s cooling performance, making it an essential upgrade for any MX-5 enthusiast.

Pros:

1. Temperature Regulation: The SkidNation MX-5 Premium Coolant Reroute Kit effectively regulates engine temperature, ensuring that the engine runs cooler, even during demanding conditions or extended periods of high-speed driving.

2. Reduced Hot Spots: One of the most significant advantages of this kit is its ability to eliminate hot spots in the engine, which can lead to overheating and potential damage. The reroute kit evenly distributes coolant flow, preventing localized overheating.

3. Improved Reliability: With the elimination of hot spots and more consistent cooling, the MX-5’s engine is now more reliable, and I have peace of mind knowing that I can push the car harder without worrying about overheating.

4. Easy Installation: The kit comes with clear and detailed instructions, making it relatively straightforward to install for someone with basic mechanical skills. The included hardware and gaskets ensure a leak-free and secure fit.

5. Quality Components: The MX-5 Coolant Reroute Kit features well-crafted components that are built to last, even in demanding driving conditions.

Cons:

1. Cost: While the performance gains are significant, the price of the MX-5 Coolant Reroute Kit can be seen as a downside for some, especially for budget-conscious car owners. However, the benefits it offers make it a worthwhile investment.

2. Space: This kit will occupy a larger portion of the engine compartment.

3. Serviceability: Shifting the thermostat housing to the rear will increase the level of difficulty when it comes to replacing the thermostat.

In conclusion, the MX-5 Coolant Reroute Kit is an excellent addition for any Mazda Miata owner looking to enhance their car’s cooling performance and reliability. The reduction of hot spots, even cooling, and straightforward installation make it a valuable upgrade for both track enthusiasts and daily drivers. While the initial cost may be a consideration, the long-term benefits in engine protection and performance improvement make it a wise investment for any Miata owner.

Additionally, it enhances the visual appeal within the engine bay. 😉

Rating: 8/10