BMC Air Filter is one of the worldwide leaders in the production of air filters and intake systems in the automotive sector, both road and racing.
The company operates in both the Aftermarket, thanks to a vast range of replacement air filters, and in OEM, designing and developing as Tier1 entire filtration systems (air-boxes) for the major global carmakers.
BMC is headquartered in Medicina (Bologna), in the heart of Motor Valley, and has branches in China, India and more than ninety distributors throughout the world.
For over twenty years now, BMC has been working together with the most prestigious international racing teams and has contributed to win 13 Pilots titles and 14 Constructors titles in Formula1, 5 World Rally Championship titles, 14 DTM Championships, 17 Le Mans 24 Hours, 5 Riders titles and 4 Manufacturing titles in MotoGP.
BMC originated in the racing world, specifically in Formula1, but in the last twenty years it has managed to extend its range of products to the Aftermarket compartment as well. The Aftermarket catalogue, constantly growing and updated, includes approximately 12,000 specific applications for automobiles and 2,000 for motorbikes.
Air filters made of cotton for standard air-boxes (replacement Aftermarket): they replace the original paper filter, are available in various shapes and sizes, specific for most automobiles and motorbikes on the market.
Conical filters for direct intake: in both the automobile and motorbike version, they require disassembly of the original air-box. These filters are available in the TWIN AIR and SINGLE AIR version.
CDA: the classical and long-established BMC carbon intake system for automobiles, available in the Universal and Specific version for various car models.
OTA: BMC’s new carbon intake system for automobiles, the direct evolution of the CDA, available in the Universal and Specific version for various car models.
DIA: BMC’s junior intake system for automobiles, made of polyurethane instead of carbon.
CRF: BMC’s latest carbon intake system designed for supercars and sportier stock cars, as well as for superbikes. This product is available for automobiles and motorbikes, in the Specific version only.
All BMC filters are made exclusively of pre-oiled cotton.
Generally speaking, vehicle such as automobiles or motorbikes require total particle filtration efficiency up to a minimum dimension of 10 micron, in order to avoid any risk of foreign bodies passing through large enough to damage the mechanical components downstream the intake system.
OEM air filters are made of paper, and their main function is to protect the engine. These filters feature high resistance to the air flow which, consequently, reduces the pressure and the engine performance. BMC’s air filters allow the passage of a greater air flow. Moreover, compared to traditional paper filters which must be replaced when carrying out maintenance, BMC filters can be re-used so that they last as long as the vehicle itself.
On the market you can also find filters made of synthetic material that BMC occasionally produces at the request of specific customers.
The main difference between BMC filters made of cotton soaked in oil and filters made of synthetic material (e.g., plastic sheet) consists in the stopping principle of impurities.
Synthetic filters allow particles to flow through the size of which is equal to that of the micro holes in the material; if follows that a filter with 80-micron hols allows the passage of all particles smaller than 80 micron, only stopping those particles that are larger than the micro hole (just to give you an idea, sand has a dimension of about 50 micron).
Cotton has a larger weft that encourages the passage of a large air flow but, through the combination of different layers of low-viscosity oil, it is able to stop all impurities from 7 micron on up.
Currently, this concept is the best solution for both a more effective filtration and for higher performance.
Replacement filters are air filters that replace the original ones (OEM) made of paper installed in the air-box of the vehicle (car or bike).
These are regenerable, high-yield filters that make it possible to improve the intake air flow rate compared to traditional paper filters, with clear benefits in terms of the quality of the engine combustion.
BMC air filters are made of a multi-layered cotton fabric soaked in low-viscosity oil, inserted between two aluminium mesh frames. The aluminium mesh is coated with epoxy resin in order to protect it against oxidation caused by fuel vapours and the humidity present in the air. Impurities are filtered by means of sieving and retention processes, in other words the interception of impurities by the cotton fibres, which are then retained by the oil.
The procedure takes place without obstructing the air flow passage, thus guaranteeing continuity of the air filter performance over time.
BMC air filters are made using a procedure called “Full Moulding” that makes it possible to obtain the characteristic red filter from a single mould, with no gluingin the corners so as to prevent any breaking.
The special rubber used in BMC’s filtration system is practically non-deformable over time and provides excellent adhesion to any air-box shape.
*Although they guarantee a greater air flow and better engine performance, replacement filters do not guarantee an increase in HP to the car (those aiming to achieve this should consider the OTA, CDA and DIA intake systems).
All BMC filters are washable and regenerable.
The filtering material is a special type of cotton soaked in low-viscosity oil that guarantees high permeability to air but, at the same time, retains the foreign particles. The filter can be washed with water and suitable detergent. Once it is washed, a think coat of oil must be re-applied.
We recommend using original BMC kits only, as other products may not be effective or may damage the filter permanently, thus invalidating the warranty.
The kit includes the special BMC detergent and an oil applicator (in the spray or dispenser version).
We recommend regenerating the filter (washing + oil application) every 20.000 – 25.000 km to ensure best performance and long service life.
This value is a rough estimate and can vary based on the climatic conditions and the ground on which the vehicle is used (sand, dirt roads, etc.).
The various steps to be carried out in order to regenerate the filtering element are indicated in the instructions contained in the regeneration kit or at the following link: https://www.bmcairfilters.com/eng/how-to-regenerate-a-bmc-air-filter/1430/p
BMC replacement filters replace original paper filters.
Open the air-box and replace the OEM filter (the two filters have roughly the same shape; simply look at how the original filter is installed and position the BMC filter in the same way).
However, to avoid any risk whatsoever, you have to be very careful not to use too much oil during the filter regeneration phase (it must not be so much that it starts to drip).
BMC air filters are sold already coated with oil.
For some models, the BMC catalogue offers two types of air filters for the same engine: standard and race.
STANDARD: these are standard replacement filters, specific for the various types of motorbikes. The filtering element (just like the car filters) consists of 4 layers of cotton soaked in low-viscosity oil. These are very high performance filters compared to the regular original filters made of paper.
RACE: BMC filters in the Race version take the classical increase in air flow rate offered by BMC products to a more extreme level. By reducing the cotton layers from 4 to 3 , the flow of air is even greater. This is the reason why the Race filters are recommended exclusively for sports use on the track, since the increase in the air flow rate may weaken the carburation (more air flowing in than is necessary) or the injection (the control unit may not be able to correctly manage the new stoichiometric ratio). To bypass this problem, it may be necessary to reconfigure the control unit, thus obtaining a significant increased in performance. Race filters are identified by the caption “race” at the bottom of the product code, and by a yellow line on the filtering element.
Conical filters for direct intake can be installed on any type of automobile or motorbike, after removing the original filter box.
If necessary, the installation can be completed with a series of flexible hoses, support hangers, reducers or silicone sleeves.
The BMC conical filters are available in two versions:
The conical filters are made of BMC’s characteristic red-coloured polyurethane, which the intake sleeve to be the particularly resistant to both mechanical and thermal stress. The special support mesh of the filtering element allows the development of filters for applications with power of up to 700HP (in the NOS or Turbo case) with no risk of deformation.
The choice of a universal conical filter depends, first of all, on the diameter the connection pipe with the engine and on the space freed up after removing the original air-box (basically a larger filter guarantees a greater amount of air flowing into the combustion chamber, with tangible advantages in terms of vehicle performance). Since engines need cool air, it is important to avoid installing the universal conical filter on the turbine and to isolate it thermally from the heat sources present under the bonnet.
In order to optimise the installation and the positioning of the filter BMC original accessories are available, such as flexible hoses, reducers and silicone sleeves.
BMC recommends that the assembly of its universal conical filters be carried out by an expert tuner(assembly and positioning may affect the performance of the kit) and, if necessary, to carry out a re-mapping of the control unit in order to optimise the new stoichiometric ratio.
CDA is the acronym for Carbon Dynamic Airbox, the most classical direct intake system made by BMC.
It is available in different universal versions (adaptable to all types of automobiles through the implementation of assembly accessories such as sleeves, reducers or other ones) and in specific versions, dedicated to particular engines and models (kits that include all accessories needed for the installation).
BMC always recommends to have the installation be carried out by an expert tuner (since the assembly and positioning may affect the performance of the kit) and to carry out a re-mapping of the control unit in order to optimise the new air/petrol stoichiometric ratio.
OTA is the acronym for Oval Trumpet Airbox.
This is the latest direct intake system made of carbon developed by BMC, an evolution of the well-known CDA.
The Direct Intake Air System (DIA) is the junior version of the CDA.
It uses the same principles and conveys the flow of air to the engine at a higher speed compared to traditional filtration systems, thus improving engine performance. The DIA consists of a plastic air-box, with an internal filter that can be washed and regenerated like all BMC filters.
Yes, it does.
Thanks to the dynamic air intake, cool air can be conveyed to the air-box at a much higher speed compared to the intake capacity of traditional filtration systems.
The dynamic air intake is made even more effective by the carbon fibre Flow Switch located inside the air-box.
The assembly of a BMC intake systems results in a significant increase in the quantity of combustive oxygen present in the combustion chamber compared to a regular air filter.
These elements guarantee a considerable improvement in engine performance, in terms of power and torque.
The CDA and the OTA are also available in various special versions, specific for individual vehicle models, and are identified by the letters "SP" present in the part number.
These are plug-and-play versions that only need to be assembled. In case of a vehicle for which there is no specific version, one may assemble a CDA or OTA (Universal version); however, additional assembly accessories may be necessary.
All the CDAs and OTAs specifically developed for a certain application are listed at the website www.bmcairfilters.com.
In any event, there are some Universal versions that can be assembled on any car (simply verify the engine displacement and dimensions) thanks to the simple use of assembly accessories, such as reducers, sleeves or hangers.
We suggest you contact your own tuner to understand which accessories you will need and how to assemble the kit on its own vehicle.
The main different lies in the material used for the air-box of the two filtration systems.
The CDA is entirely made of carbon fibre, which is the reason why it has high resistance to temperature and low thermal conductivity, allowing the air filter contained inside to be insulated against engine heat.
In this way, the cool air coming from outside the vehicle reaches the engine directly and, thanks to the Flow Switch, with minimum pressure drop.
The air conveyance principle of the CDA is also adopted for the DIA, the only difference being that the DIA structure is made of plastic material.
In order to maximise the benefits of the new air/petrol stoichiometric ratio and improve performance as much as possible, BMC recommends reprogramming the control unit following the installation of an intake kit.
BMC does not sell directly to end users. There is a distributor for each region/country, which supplies several retailers.
All BMC filters are sold with installation instructions and with the accessories needed for assembly.
The Universal versions of OTA and CDA may require additional assembly accessories in order to properly adapt to your vehicle (hoses, sleeves, reducers, etc.).
BMC recommends to have the installation be carried out by an expert tuner, since an improper assembly may not guarantee the desired performance. For example: by assembling an air intake in a particularly favourable spot, you can significantly increase the speed of the air that flows through the air-box, for a greater quantity of cool air towards the engine.
BMC does not sell directly to private customers. Contact the relative distributor to find the BMC dealer nearest you.
BMC produces various top-quality accessories:
Since 2011, BMC air filters are sold in black-coloured boxes. Should a dealer offer you a filter contained inside a white or red box, please report it by writing to the e-mail address email@example.com: these filters are no longer being sold as they are not covered by warranty.
BMC products are guaranteed for a period of two years starting from the date on which they were purchased from an authorised dealer, provided the original warranty certificate is presented and that the purchase is made within five years from the date of manufacture indicated on the warranty certificate. In case of ascertained defect, BMC shall replace the product free of charge, excluding any additional cost charged to BMC, the warranty being limited to the replacement of defective and/or non-conforming material.
Before you purchase a DIA/CDA/OTA online, if you are not certain of the distributor’s veracity or of the origin of the product itself, you can carry out a simple check procedure:
1 - Make sure the BMC brand is visible inside the carbon cylinder, printed directly inside the carbon layers, with the caption
2 - Check that the BMC brand inside the flanges (engine side and air inlet side) is printed in the fibres.
3 - Check that the package contains the accessories, in a plastic bag, with the BMC brand.
4 - Make sure that all distinctive elements are present in the box with the BMC brand, as indicated in items 1, 2 and 3 above.
CRF is the acronym for Carbon Racing Filter.
These are special carbon intake systems designed for the best sportscars and superbikes available on the market, specifically conceived to optimise the fluid dynamics, improve combustion and, consequently, the performance.
The BMC replacement filters replace the original filters but it is recommended to check with the manufacturer of your automobile/motorbike as well as to verify the regulations in force in your country with regards to any limitations.
Replacement filters can be easily removed for possible checks, service or revisions.
BMC’s intake systems are considered “racing” products, hence we recommend that you check the regulations in force in our country with regards to any limitations.