It's called a firewall, but truth be known, a car's firewall is nothing more than a metal divider between the engine and the cockpit. These bulkheads are punctured and have a multitude of wires, hoses, and cables running through them. Often, the holes are not sealed, leaving open gaps between engine and driver. In the event of a fire, fumes and flames can easily enter the cockpit, making a bad situation worse.
Enter Alabama-based manufacturer Unique Fire Stop Products. Run by IMCA racer Mike Tobias, the small company has taken its commercial firestopping technology that is used in buildings and adapted it for the motorsports industry. It's called the Automotive FireStopper System and has already won acceptance from IMCA, NASCAR, and SCCA.
The Automotive FireStopper System comes in a standard or heavy-duty version. The heavy-duty version is specifically designed for racing. The system features three items: Unique Expanding Foam, FireStopper Sponges, and FireStopper Sleeves.
The sleeves come in three different sizes and are specially designed to seal off the holes that your wires, cables, and hoses pass through. They feature an intumescent putty, which swells and seals off the opening in the presence of fire. The putty activates when the cable jacket burns. As the putty swells, it completely seals the opening.
The Unique Expanding Foam acts similar to the expanding foam available at home improvement stores. However, unlike those home improvement foams, Unique Expanding Foam is non-flammable and will not emit toxic gases in the presence of fire. Using expanding foams (such as Great Stuff) and silicone sealants in racing applications is exceptionally dangerous. In the event of a fire, those materials will release toxic gases that you, as the driver, can breathe. If the fire doesn't get you, the toxic fumes will. That's why Unique created its Expanding Fire Stop Foam. Its non-flammable formula will expand approximately seven times the nozzle size, sealing small cracks, seams, and openings. While it was originally developed for use in commercial buildings' fire-rated walls, it works perfectly in race car applications. Once the foam has cured, you can use a sharp razor to trim the paintable material flush with the surrounding sheetmetal.
In order to complete the "System," Unique needed a way to block flames from an engine or fuel cell fire in pass-through holes where movement was required, such as around the throttle linkage or a steering column. The solution was the Fire Stop Sponge. This sponge won't swell in the presence of heat, nor will it catch fire, allowing for the continual movement of the different components. Unique currently offers the sponge in four sizes.
When used in conjunction with one another, the three components of the system will completely seal off the engine compartment from your cockpit. Not only will you be protected from fire, but also the heat and fume transfer from engine bay to driver's cockpit is drastically reduced. Unique has assembled these three components in a convenient kit that retails for around $150 from Speedway Motors.