If you were to select one type of product produced by the Bayerische Motor Werke (BMW) to hold up as an example of their engineering prowess, it would have to be their inline six cylinder engines.
While much of the rest of the automotive worlds has abandoned the inline six for the more compact (especially for front-wheel drive applications) for some version of a V6, BMW has held tight to its commitment to the smoother-running straight six that requires no balance shafts or unusual timing needed to calm the otherwise rough-running V6 configuration. In fact, BMW has been experimenting with V6 designs for a number of year but are never able to get one to meet corporate noise and harshness standards.
While over the course of nine years, BMW has developed and replaced its six-cylinder designs, they have relied upon the same basic air box configuration, into which the K&N 33-2292 air filter is the perfect fit.
The first applications for the K&N 33-2292 began in 2003 with the BMW 520i, 525i, and 530i, which were fitted with BMW’s M54 is a straight-six DOHC engine. The M54 uses an aluminum block with cast iron liners and an aluminum cylinder head with cast iron cylinder liners. Further, the M54 features variable valve timing to both camshafts (dual VANOS in BMW speak) and a dual length intake manifold, which was named DISA by BMW.
The final application for this long-lived air filter design was the 2010 and 2011 BMW 630i. Despite the passing of eight years, the filter configuration, available as K&N 33-2292, remained the same even though the N52 engine was quite different.
Like the BMW M54, the BMW N52 is a straight-six DOHC engine. Compared with its M54 predecessor, the N52 features variable valve lift (ingeniously named Valvetronic by BMW), a lighter magnesium engine block and an electric water pump and a variable speed oil pump. Like the M54, the N52 uses an electronic throttle control, the VANOS variable valve timing to both camshafts and the dual length DISA intake manifold.
These are just the bookends of the applications for this filter. In between are cars as diverse as the Z4 and models of the 3, 5, and 7 Series.
Regardless of whether your BMW is powered by a 2.0 L, 2.5 L or 3.0 L engine, installing a K&N filter provides an increase of up to 50% incremental air flow to the engine. By increasing the flow of air, it can result in a more responsive throttle and improved torque at all points of your BMW’s operating range.
K&N air filters are assembled from several layers of oiled cotton filter media, which accounts for their long service life. Also the oiled cotton medium allows for increased air flow as well as offers excellent filtration characteristics. Often OEM and less-expensive filters are made from more restrictive paper media which can actually limit the output potential of the engine. The performance of each filter design is verified through K&N’s in-house efficiency testing, which follows strict ISO 5011 standards, and confirms that K&N filters provide a high volume of intake airflow without sacrificing engine longevity.
And once you’ve installed your K&N 33-2292 air filter you’ve eliminated the need to purchase and replace paper filters for the life of your six-cylinder BMW 3, 5, 6, 7, and Z4 series. The only maintenance necessary is one you can do yourself in just a short time. At intervals of 50,000 miles or about 80,000 kilometers (depending on your driving conditions) simply use a K&N air filter cleaning kit to easily clean and re-oil your air filter — returning it to like-new performance levels. Your one K&N air filter is designed to last the lifetime of your vehicle, which K&N guarantees will perform for up to 10 years or 1,000,000 miles without requiring replacement. For full details visit the K&N Million Mile Limited Warranty.
You can order the filter simply by using the part number 33-2292 and while you’re at it, grab an air filter cleaning kit, part number 99-5000.
For more information on this panel filter, check out K&N.