Temperatures in the Miata can soar while on track. Hot weather aside, the lack of air flow inside the car coupled with the intense heat from the engine and exhaust can turn the passenger compartment into an oven. Couple that with a full race suit, gloves, and helmet, and it’s downright hostile!
Many racers use a “cool suit” setup, which is a shirt with tubing or bladders that has cold water from a reservoir pumped through it. Reading others’ DIY attempts led me to simply purchase a FAST shirt (significantly more tubing than the cool shirt branded items.)
To save a significant chunk of money, I built the reservoir and pump setup.
The cooler was from Amazon, though other organizations sell similar models. It’s sold as a “dry box/cooler.” I fit a 12V bilge pump to brass fittings – easily the most expensive components – and vinyl tubing.
Rather than buy the fittings compatible with the FAST shirt, I opted to cut them off and fit them with similar and much cheaper dry-break quick disconnects. The water lines, along with a power switch wire, are run inside a piece of adhesive joined insulation.
The cooling umbilical ends right next to the driver’s seat. I plug the shirt into the fittings and hit the switch, and am soon being chilled by water from the cooler in back.
I used eye bolts and ratchet straps to hold the cooler down, but a welded tray would hold it more securely.
It’s definitely something I should have added to the car a long time ago. The difference in stamina and comfort are very significant!