Our Stage 3 airflow kit is a monster thanks to its brushless tech. But those fans are expensive, so we decided to see what we could do with just one.
Brushless? Why haven't you seen that elsewhere? These fans aren't usually available to the aftermarket, they're used by OEs and the military. Our long-standing relationship with Spal and our ability to create a complete solution means we can bring them to Miata owners!
So what's the advantage? First, the fan has a variable speed and an intelligent controller so it can deliver as much or as little airflow as required, from a slight whisper to a hurricane. It's tied into the coolant temperature, so it can anticipate problems and prevent the car from getting hot in the first place. This means less electrical draw and more power available at the wheels when the car is at normal temperature. It also avoids a big startup surge that can drag down your electrical system for a moment or blow fuses. In fact, it's so subtle you may never actually notice when they're running most of the time.
Where they really shine is their ability to pull through multiple heat exchangers. Most fans are rated in free air, but that's not doing you any good. You have a radiator and maybe an intercooler and possibly an AC condenser and maybe even an oil cooler all stacked up in front of the fan, so it's having to pull hard to get air through that stack. A standard radiator will give about 150 Pascals of pressure at the fan and it only goes up from there. You can see from the chart how our brushless kits stack up. Those motors are strong. They're also built to military specifications, so they're highly waterproof and vibration resistant. Naturally, it's mounted on a custom shroud with bypass flaps.
So what's with the single fan variant? Well, by going with a single fan we can also go with a large diameter fan. These high-torque brushless fans are quite deep, and the central location of the single fan helps quite a bit with fitment. It also cuts down the cost fairly significantly. When we looked at the numbers, we saw that it slotted really nicely in between our Stage 1 kit and the Stage 3 - so our single fan experiment became the Stage 2.
This kit will fit with "normal" installs of our turbo kit and front sway bar, but if you have extra / bigger parts in front of the engine (e.g., a giant sway bar) it's a good idea to check clearance. This fan is about 2.25" (measured straight / horizontally back) from the fan mounting bosses at the sway bar. It's mounted at an angle, so it's a bit less at the bottom and a bit more at the top.
Certain ECUs such as the Hydra and MS3 can control the fans directly so they do not require the standalone controller. Stock ECUs, MS2 and the FM221 will require the controller. The fans will not work without PWM control of some sort.
The non-crossflow variant is designed to fit an NA radiator. If you're going to fit it on an NB radiator with the horizontal fan brackets at the bottom, you will need our adapter kit. The crossflow version does not need these brackets.
Please note that a radiator is not included.