The Oval Trumpet Air box (OTA) is a high performance aspiration and filtration kit from BMC Air Filters. It is fully designed and manufactured by the BMC race division in Italy, the same team which is constantly developing new air filtration systems for teams in many motorsport categories including Formula 1.
The OTA is a complete kit for engine air aspiration and filtration. The device is composed of an oval-shaped air box in carbon fibre containing a cylindrical air filter with dynamic inlet. The OTA kit totally replaces the original car filtration air-box. With its dynamic inlet the OTA provides a constant and highly rated quantity of air to the engine, taking advantage of the dynamic effect of the air pressure.
In addition to its oval shape, offering high installation versatility, the OTA system introduces internally a solution which optimises the fluid dynamics of the air to the engine. The innovative “Trumpet”, which is situated inside the air box, optimises the air flow thanks to its unique shape, resulting in the reduction of turbulence. This solution reduces the air pressure drop and, at the same time, takes advantage of the dynamic pressure of the air caused by the speed of the moving car.
The BMC air filter within the OTA is composed of a metallic mesh containing an oiled four ply cotton filtration material. This ensures a high level of filtering efficiency with guaranteed containment of all impurities down to 7 microns, where paper filters generally only offer filtration of particles of 10 microns. This unique filtering element traps even the minutest particles ensuring maximum protection from dirt and sand particles, petrol fumes and oxidisation.
BMC air filters are also designed and produced to ensure a higher air flow than original filters, producing less than half the pressure drop when compared to paper filters. BMC air filters allow more air into the engine in comparison, while providing better protection. As cotton is a natural material which can be reused several times the filter can be washed with a special detergent then re-oiled, saving the cost of changing the air filter each time the vehicle is serviced, also reducing environmental waste. BMC air filters have a general lifespan equal to that of the vehicle.
The OTA system delivers better filtration, combustion and performance, consequently improving torque (NM) and maximum power (HP) through the whole engine RPM range, while additionally OTA delivers a sports sound.
The OTA kit range features different air box dimensions and various connection parts and is available in several universal fit kits which can be installed in different vehicle models. There are also specialised kits for selected models like the Land Rover DEFENDER TD5 (ACOTASP-11WP). There is also a range of Waterproof kits available in the OTA line, specifically designed for heavy off-road conditions and hard environments (water, desert sands), and are compatible with most snorkel systems.