A number of people have been asking about performance air filters and after Cold Air Induction Systems and which one is best for their vehicle. I have to say right off I have never been a fan of aftermarket filters of this type and we will go into some detail about why you probably shouldn’t use one but the primary thing is that engineers at these large car makers know what they are doing. They spend many millions of dollars designing the air flow systems of their vehicles and use both computer based and real flow bench results to find the optimal equipment for their engines. If you think for a minute with all of the push for fuel economy and using smaller engines with higher horse power that an engineer is going to deliberately restrict the flow of an engine for any reason or not find the best setup then you are foolish.
The next thing that you have to consider is that these washable filters do clog up and no matter how well you wash them they will never flow like a new filter. If they did have a higher flow rate because of the materials used then you can probably expect that some of the fine particles are not being caught.
When are Aftermarket Air Filters the Right Choice?
Probably the best application of aftermarket products that aren’t OEM reproductions is using them on custom builds. If you are building an actual race vehicle and the air cleaner / induction system and filter will not fit in its normal position or if you are building something like a dirt track racer then this would be the best application.
This is not to say that they will perform better and give you more horsepower but that they are able to be fit into different applications and routed differently with custom made parts.
What about Performance Horse Power Claims of these Parts?
Like we talked about there are applications for these products and your vehicle might be one of them but the funniest thing that I see is when someone takes apart their induction system and then places a short pipe with a filter on it that is often sucking up air right next to their header. This is really pitiful because the OEM equipment normally runs a pipe either to an inside fender or up around the radiator to make sure fresh cold air is being used and then someone buys one of these chrome pipes and throws a $50 filter on it and thinks that is a better solution.
Right there is a real issue and it shouldn’t be overlooked however some of these filters do use the OEM pipe to route air through it and then the only difference is the material that is being used and whether it actually flows better.
What are the real downsides to using After Market Performance Air Filters?
Most of these products require that you oil the filter material and this is a really bad idea for your air induction system. First of all you never really know how clean you get the filter when you wash it. Second you can never accurately apply the oil that they suggest and finally even if you get both of these things correct you have a high probablility that over time dirt and oil will begin to clog up your sensors.
Some of theses sensors can be cleaned but thats really not what you should be doing. You shouldn’t be making more work for yourself and maybe costing yourself some really expensive parts just because you think maybe its a good idea because some marketing company made a really cool commercial that convinced you to tare out millions of dollars in research and stick a straight tube with an oiled filter in your hot engine bay.
The next problem is that normally these products will pass dirt easier than the finer multi-layer paper filters. Paper isn’t perfect for all applications but it is a refined science to remove particles from the air.
Final Note
Like I said I have never really been a fan of aftermarket air filters or induction systems.
Yes some of them can look beautiful on your classic vehicle with that brand new big block that you forced under the hood but normally on newer vehicles that have been optimized by factory engineers the need for them is not existent.
So before you get carried away like most first time builders do you should really consider where you are spending your money, what type of return you will get for it and finally what problems these parts might cause.
I can remember as a teen the first thing you do to your car is get headers and an air filter and then tires and wheels. Honestly none of that is really going to do much for you when you consider the money could be spent better to provide much more horse power and durability.
You should use these products for the correct application. If you are replacing a non existent induction system on a car you are restoring, if you are building a full on race vehicle that probably doesn’t even have a hood on it but not just because your buddy bought one and they look pretty. Are you really going to get another 50 or 100 HP out of it? Nope maybe you might maybe but probably not get another 5hp that is not even measurable during normal conditions. So then save your money for something else that will get you that performance boost.