Pressurized Swirl Header Tank
Whether you race, do track days, autocross, or just enjoy your Lotus on the street, removing heat from the engine is a critical function to reduce engine wear and maintain power.
It's no secret that aeration of the coolant hinders its ability to absorb and transfer heat. The coolant becomes aerated from localized boiling around the cylinder walls (creating a layer of steam around the cylinder walls) in addition to turbulence from the water pump and coolant passages.
NASCAR, Formula 1, and other race series have developed great strategies involving pressure and swirling to help combat these issues, which have long since trickled down to mere mortals.
The first is with pressure. Simply put, the more pressure, the better. Pressure not only increases the boiling point of the coolant, but it also reduces the size of the air bubbles/pockets in the system. Higher boiling temperatures equate to less fluid boiling and therefore less air in the system. Reducing the air bubble size from greater pressure reduces the size of the steam layer around the cylinder walls, which helps extract more heat from the engine itself!
The second is the simple concept of swirling the entire cooling mass. Swirling forces the heavy coolant to outer region of the tank forcing the lightweight air to separate from the coolant and collect toward the center of the tank.
The combination of swirling the coolant and adding more pressure to the system will help to ensure you're getting the most heat out the engine and transferred to the radiator where it can be dissipated.
Our pressurized header swirl tank is expertly welded and complete with a site tube, Lotus specific bracket, hoses, and hardware.
An optional regulated air inflator tool available separately. This air filler can be dialed into your desired pressure under 20PSI to pre-pressurize your tank for greater operating pressures. It is NOT required, but makes quick work of filling your tank to a desired pressure.
The tanks are shipped with 30PSI caps. We typically run 40PSI in race cars. Please note that running pressures in excess of 30PSI is not recommended unless you have replaced your OE radiator and hoses.
NOTE: This system is designed around upgraded/ aftermarket intake systems. If attempting to install on a stock configuration, the airbox lid will interfere with the header tank. Installation may still be achievable with some adjustments.