DIY Cool Suit System by Ron Earp

Ron Earp

I had a couple of people from the Improved Touring forum write me about details of making an in car “cool suit” setup. I figured I’d detail that here and try and contribute a bit to the “How To” section.

If you spend any time in a race car oh, say South of Maine USA, then you need to know what a cool suit is. Basically, you wear a t-shirt with tubes sewn into while an electric pump circulates ice cold water through the tubes thus keeping you nice and comfy on hot days. Clearly you can vary the temperature of the coolant by using various amounts of ice/water, but down here in balmy North Carolina I like the cool suit with ice water pretty much year around.

Over time heat really causes your concentration to decline. Wearing a three layer race suit, helmet, gloves, nomex, and so on when the outside temperature even hits 65F is, to me, uncomfortable. Throw in some 90F+ days, high humidity, and a tight cockpit and I think you’ll see how one of these devices comes in handy.

Cool Suits are routinely sold as a complete system for about $400. Here is a link to such a system:

Fresh Air Systems*Racer Series Cool Suit System*-*SafeRacer

I think they are expensive when you consider the system isn’t hard to duplicate. My goal here is to outline the components and then give you sources for them – that is the hardest part – finding the cool shirt with the tubing sewn in and the dry break connectors.

A basic system consists of:

·An ice cooler
·A “Cool Shirt”
·A water pump
·Dry break connectors

First thing you should get is a cool shirt. For the shirt I got a FAST shirt for $70. Contact the company via [email protected] or 1-847-439-6004, I spoke with Nick and maybe he can help you.

Once you have the shirt it’ll define the dry break connectors you need. More than likely they will be the ones shown on this link:


They are also available via other sources such as:


Bear in mind what you want to do is have hoses mounted in your car that are more or less fixed in place that you can plug your shirt into.

Once you have the shirt and dry break connectors then you just need to engineer your cooler box location, mounting methods, type of pump to use, and put it together. Here are some comments and photos of the system I made for my racing Z.

I used a small beer cooler as shown in the photos. It worked well and I added a gate latch to the cooler so that it’ll be positively latched and I won’t have problems with water coming out of the top of it.

The pump I have shown there is a $10 Walmart bilge pump and it works like a champ. I have it wired to a switch and 5 amp breaker on the dash.

I have the pump connected to additional dry break connectors in the lid of my cooler, but this is not necessary. You could simply make holes in the lid for the hoses to pass through and use silicone rubber to seal around them. You might need some additional hose of various ID to make sleeves to get your hoses to attach to the bilge pump. The water return is just a hose coming into the top of the cooler.

You can strap your cooler system in if you like, but I bolted mine in place and insulated the bolts so that they don’t become heat transfer devices to the chassis.

I made one additional “modification” and attached a drain hose to my car. At the end of the weekend I can unplug the output hose from the pump and plug this hose in and then turn the system on. This hose will allow the system to pump itself out to the drain under the car.

When running the system I fill it about 1/2 to 3/4 way full with ice/water. Mine system seals pretty well, but it could be better. I think I'm going to run a small bead of silicone or caulk around the top of the cooler with the lid open and let it dry. That would form a compressible seal which should make it good and tight.

Oh, and I don't have the fancy insulated hoses that come with the high buck systems so I wrapped the hoses with insulation from Lowe's home Improvement. You might can source those hoses, and if you do let me know. mine work fine though and I don't think I'm losing anything that isn't compensated for by the large capacity of the system.

And that is about it – pretty simple huh? More or less a fun little project you can do on your on with household materials. The system I have cools as good as the $400 system (told to me by those that have driven my car and own the $400 systems) but the total expenditure, including the shirt, was right at $100. It has enough capacity to keep you nice and chilly for at least a 45 min race, which is about perfect.