Long established as an oil filter medium, but I've never seen it mentioned as an air filter supplement.
Not perhaps the most efficient filter supplement, but easy and cheap. If you have a restriction guage to check it, and stay well within its allowable range, I can't see a problem. Even if it only functions as a "rock catcher" that's a benefit with no obvious downside.
I tried four layers of washroom paper hand towel to get my home-made restriction guage/decoker to work, giving a restriction of about 4.5 inches of water.It didn't seem to affect drivability. Don't know about fuel consumption yet.
I'll try actual toilet paper (which might be more convenient) next time I drive the car. Failing that I'll cut the layers to two.
Admittedly I've only tried it with the "classic" circular filter, and it might be more difficult with the commoner flat-panel design, but not impossibly so, I'd have thought. Individual folded towels might work better there.
There is a sort-of-precedent in the literature, in that the oft quoted paper on the effects of filter restriction used disposable shop towels to simulate filter clogging, and they did get some filter damage, but they were doing WOT tests with a level of clogging of more than 10 inches of water, which would trip a filter minder and indicate replacemnt.
https://www.fueleconomy.gov/feg/pdfs/Air_Filter_Effects_02_26_2009.pdf
Not perhaps the most efficient filter supplement, but easy and cheap. If you have a restriction guage to check it, and stay well within its allowable range, I can't see a problem. Even if it only functions as a "rock catcher" that's a benefit with no obvious downside.
I tried four layers of washroom paper hand towel to get my home-made restriction guage/decoker to work, giving a restriction of about 4.5 inches of water.It didn't seem to affect drivability. Don't know about fuel consumption yet.
I'll try actual toilet paper (which might be more convenient) next time I drive the car. Failing that I'll cut the layers to two.
Admittedly I've only tried it with the "classic" circular filter, and it might be more difficult with the commoner flat-panel design, but not impossibly so, I'd have thought. Individual folded towels might work better there.
There is a sort-of-precedent in the literature, in that the oft quoted paper on the effects of filter restriction used disposable shop towels to simulate filter clogging, and they did get some filter damage, but they were doing WOT tests with a level of clogging of more than 10 inches of water, which would trip a filter minder and indicate replacemnt.
https://www.fueleconomy.gov/feg/pdfs/Air_Filter_Effects_02_26_2009.pdf
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