Hi Rob,
I recently bought a 2010 Honda Accord 4 cyl. coupe and while I simply love the car, I have minor regrets about not going with the V-6 for the extra power.
After doing a cursory search online, I've found a number of websites that promise more horsepower better mileage just by changing out my air filter.
Is it possible that I will see a benefit in added horsepower and improved fuel efficiency by changing my air filter and if so, why doesn't Honda supply these "improved" air filters? And if I do install an aftermarket air filter, will it negatively affect my warranty?
Thanks in advance for your thoughts, Tony
Yes and no, Tony. High flow air filters have been around for a long time, and they have consistently been one of the quickest and cheapest ways to boost engine performance. However, these gains were more noticeable when intake systems and OEM air filter housings were nowhere near as efficient as they are today. These low flow filters removed one of the restrictions in the very restrictive intake passages that delivered outside air to a carburetor.
Nowadays, these air passages are far more efficient with (mostly) radiused corners between the air filter housing and the intake manifold. However, that's not to say that this design can't be improved upon. These new filter designs are made of a filter media that is inherently high in mass air flow handling capacity and in many cases come with an optional ducting and housing assembly that completes the package. The other cool thing about these filters is that most of them are cleanable. That is, you have the ability to remove the filter and clean it with spirits and re-install in the housing, saving the cost of purchasing a new filter while keeping the old filter out of the landfill – win, win.
Because of this design, you will notice an increase in engine performance and if you keep off the throttle, you'll notice a slight increase fuel economy as well. The problem is: many people like the renewed sound that the engine makes after the installation of one of these devices so they tend to stuff the throttle more than normal. I'm asking that you keep this in consideration because after I've recommended these low flow filters, I get complaints that the fuel economy has gone down.
It's unlikely that auto makers will install these filters at the factory due to the extra cost. Imagine a manufacturer like Honda that sells about 1.5 million vehicles in North America having to add build costs of (on the low side) $50 per vehicle. That's a $75-million hit to the bottom line that has to be passed along to the consumer.
As for warranty issues, air filters are considered a consumable so of course, they are not warrantable. As for effect on your warranty, you should not have an issue, but as I always say, check with your dealer or the manufacturer whenever making modifications to a vehicle.
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