K&N Air Filter and Shell gas makes a difference?

[smalldisplacementfreak]

Hi all,

I replaced my stock air filter with a K&N air filter and switched gas from Costco to Shell. I've noticed that I now average 35+mpg on '03 Honda Civic EX sedan. I used to average 32 - 33 mpg. I haven't changed my driving style, so I'm attributing the increase in efficiency to the filter and fuel.

Has anyone been in a similar situation?

Thanks and take care!

-SDF

[GasSavers_Red]

Could just be a new clean air filter that did the trick.

[SVOboy]

Welcome to the site! It would be hard to say with something so small...

[Jim Dunlop]

I prefer Shell gas; apparently it's in the "Top Tier" group of oil companies which have a certain detergent content in the fuel.

Recently I switched to 93 Octane Shell V-Power because the lower grades may contain up to 10% Ethanol. After a couple/few tanks we'll see if it made any difference. Then again, the mercury is falling so it will be hard to tell.

[StorminMatt]

Originally Posted by smalldisplacementfreak

Hi all,

I replaced my stock air filter with a K&N air filter and switched gas from Costco to Shell. I've noticed that I now average 35+mpg on '03 Honda Civic EX sedan. I used to average 32 - 33 mpg. I haven't changed my driving style, so I'm attributing the increase in efficiency to the filter and fuel.

Has anyone been in a similar situation?

Thanks and take care!

-SDF

It's probably the air filter that made the difference. Stock style paper air filters are notoriously restrictive. And ANY restriction in the intake or exhaust increases what is known as 'pumping losses'. Specfically, a restrictive air filter is going to increase the power the engine must expend to take in air - power that could be used to power the car itself. By reducing pumping losses, the engine need not produce this extra power to breathe, which results in lowered fuel consumption. I should also add that you would probably get even better fuel economy if you go with a complete intake system with a cone-style filter. An exhaust system and header would also help.

[MetroMPG]

At the low average engine load conditions that most fuel efficient drivers operate, the most significant "restriction" in the system isn't the air filter or intake plumbing, it's the throttle plate itself. It's unlikely that switching to a K&N would have made any difference. Unless, as Red points out, your old filter was completely plugged up.

Welcome to the site, though. Nice bike!

[bowtieguy]

Originally Posted by smalldisplacementfreak

Hi all,

I replaced my stock air filter with a K&N air filter and switched gas from Costco to Shell. I've noticed that I now average 35+mpg on '03 Honda Civic EX sedan. I used to average 32 - 33 mpg. I haven't changed my driving style, so I'm attributing the increase in efficiency to the filter and fuel.

Has anyone been in a similar situation?

Thanks and take care!

-SDF

next time(not too late to start over), try one mod at a time over several tanks while eliminating as many variables as possible. i.e. drive the same routes, same weather(avoid testing during seasonal changes),same driving style, etc.

i have, however, notice that shell yields slightly higher FE for me(no ethanol).

[MetroMPG]

Originally Posted by theclencher

k&n ads don't apply either

Thing is, you won't find a K&N ad that claims their filters will improve fuel economy. Only testimonials. (At least that was true last time I checked their site.)

There's a good reason for that, and it takes the form of of government fines for misleading advertising.

EDIT: just checked the K&N site again, and in the "Fuel Economy" section http://knfilters.com/filtercharger.htm) , they do NOT claim improvements in FE, except the caveat about dirty filters. Instead they only link to the testimonials.

And of course invite you to test it yourself! Because the average joe is so likely to have the time/knowledge/inclination to accurately test it after parting with his 40 bucks or whatever.

[Rick Rae]

Welcome aboard!

When I switched to K&N there was no noticeable FE improvement. But that was back when I was still making major adjustments to the nut behind the wheel, so it might have gotten lost in the noise. I did keep the paper filter and plan to do an ABA someday.

As for Shell gas, I'm running a study as we speak. I was originally looking for any evidence of "degunking" thanks to using V-Power, but people brought up the higher-FE-with-Shell thing and lately it's morphed into looking for proof of that. The discussion includes figures from other people as to what they noticed when using Shell versus other gasolines.

Some folks are sure the same thing is visible in my numbers too, but I'm not ready to say that yet. I want to see clear trends that are above the noise floor without question, so a few more cycles of testing are needed.

But every vehicle is different, and if you see significant improvement based on those two factors, that's great. Take advantage and run with it! Consider doing some ABA testing, though, to make sure the change is coming from what you think... maybe it's partially (or completely) from something else that you can tweak to get even better numbers!

Rick

[trebuchet03]

Originally Posted by theclencher

prove it

k&n ads don't apply either

Ditto

Also, prove they are at least equivalent in filtration. After all, it's first job it to filter - not get your better FE somehow

In any case, there's a rather good test on the autospeed site on air filters... They tested a new filter, and a extremely dirty filter, no filter etc.... The difference between the dirty and clean filter was very little.