The power increase provided by a performance air filter varies by engine size, vehicle type and a number of other factors. Most manufacturers claim their filter will provide a 2% to 4% increase in horsepower. While the exact number may not be known, the power boost will be noticeable immediately after installation.
Most vehicles will experience at least a 1-2 mpg improvement in their fuel economy after installing a performance air filter. This results from more efficient fuel burning that gets the most power from every drop of gas.
It's also possible that your driving style will change with the increased horsepower provided by a performance air filter. It is not uncommon for drivers to take advantage of this newfound power by slanting more towards a style of hard driving, which can negate any gas mileage improvements. If you leave your driving style unchanged, though, you should get some relief from soaring gas prices.
No. Performance air filters are designed to replace the exact shape filter you're currently using. No modifications of any kind are necessary to install a performance air filter and begin reaping the benefits. Installation may require or recommend removal and reinstallation of some stock parts for cleaning; ensuring your new filter makes the tightest possible seal with the air box.
Most performance air filters are pre-oiled with the correct amount at the factory, making your filter ready-to-use right out of the box. Pay special attention to the directions included with your air filter, though, as each manufacturer is different.
Performance air filters that don't use oil at any stage have cleared development and are hitting the market. Use caution, as oil-less filters are a special case. Oiling a filter which does not use oil, adding oil to an already-oiled filter or over-oiling a performance air filter after cleaning can cause serious damage. And, your filter's warranty will almost certainly be voided.
No. Engines can only take in a fixed volume of air, depending on the size of the engine. Stock air filters and intakes deprive the engine of this maximum air flow, robbing both fuel and power efficiency.
Adding higher volumes of air to the mix allows a more efficient fuel burn, which in turn improves power and mileage. Modern engines sense the increased air flow, and respond with the correct amount of fuel. This not only achieves maximum efficiency, but guarantees the safety of extra air flow. In terms of performance, extra air can only help your engine.