2020 test6 productsAuto Parts & Repair
Which Car Air Filter Brand Wins?
A head-to-head test of 6 car air filter options with the measured results for each. See how they ranked and watch the full test video.
Ranked first
EPAuto
Price shown in test: $8.87
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The measured results
Every number below is read straight from the test. Scroll sideways to see all measurements. Products are listed in the order they finished.
| Product | Construction | New Filter Airflow | 0-60mphTest(2003 Suburban, best of 2 runs) | ContaminationTest(smallParticles 1-5 micron) | ContaminationTest(largeParticles 5+ micron) | Static Pressure After Contamination |
|---|---|---|---|---|---|---|
| 1EPAuto$8.87 | 80 pleats (most of any filter tested), 2 layers of adhesive, 507 grams | static pressure 2.76 in H2O, airspeed 54.7 mph (baseline with no filter: 59.4 mph airspeed, about 0.96 in H2O static pressure) | 9.4s and 9.4s, best 9.4s, initially the time to beat | phase 1 (flour spread) +107; phase 2 (half-second air pulse) 165; phase 3 (1 min continuous airflow) 587 | phase 1 +76; phase 2 61; phase 3 26 | increased from 2.76 to about 3.49, the lowest (best) final static pressure of all six filters |
| 2Fram Extra Guard$12.47 | 76 pleats, 3 layers of adhesive, 441 grams, larger pleat hole size than EPAuto | static pressure 2.75 in H2O, airspeed 54.9 mph (best airspeed among filters until K&N was tested) | 9.5s and 9.5s, best 9.5s (chapter metadata confirms '9.5 seconds average & best time'), slightly slower than EPAuto | phase 1 173; phase 2 361 (more than twice EPAuto's phase-2 count); phase 3 697 | phase 1 126 ('next to last' place); phase 2 252 (about four times EPAuto's phase-2 count); phase 3 166 (worst/last place of all six filters) | increased from 2.75 to a figure captioned '23.82', almost certainly a caption-mangled decimal for approximately 3.82 based on the closing ranking (EPAuto best, then K&N, then Fram); kept the literal caption value and flagged rather than silently corrected |
| 3AC Delco$16.23 | 76 pleats, 3 different adhesive applications, mesh offset in three areas, 577 grams (heaviest filter tested) | static pressure 3.03 in H2O, airspeed lower than Fram's 54.9 mph (exact mph not stated) | 9.4s and 9.6s, best 9.4s, matched the fastest time at that point in testing | phase 1 76 (better than EPAuto and Fram); phase 2 326 (better than Fram, not as good as EPAuto); phase 3 697 (tied with Fram) | phase 1 58; phase 2 182; phase 3 157 ('next to last' place, just ahead of Fram) | increased from 3.03 to 4.18 |
| 4Purolator One$21.59 | 75 pleats, a few lines of adhesive, part of the filter media appeared pressed, 451 grams | static pressure 3.09 in H2O, airspeed 54.6 mph (slower than Fram) | 9.8s and 9.4s, best 9.4s, matched the fastest time despite a notably slow first run | phase 1 count actually decreased by 13 from the baseline in the test box; phase 2 increased to 116 (best of all filters at this phase); phase 3 increased by 468 | phase 1 unchanged from baseline (essentially 0 particles got through); phase 2 increased by only 35 (best of all filters at this phase); phase 3 increased by 14 | increased from 3.09 to 4.48, one of the two highest post-contamination pressures, framed by the narrator as evidence of superior contamination trapping |
| 5WIX$22.12 | 72 pleats (fewest of any filter), no adhesive applied to the filter media (unlike all other brands), four areas of wire mesh extending outward, 413 grams (lightest filter tested) | static pressure 4.07 in H2O (highest/most restrictive of any filter before K&N... actually the single highest new-filter static pressure of all six), airspeed 52.1 mph (lowest of any filter) | 9.4s and 9.3s, best 9.3s (chapter metadata confirms 'Best 9.3, average 9.35') | phase 1 count decreased by 2 from baseline; phase 2 increased by 43 (best of all filters at this phase); phase 3 peaked at 401 | phase 1 count decreased by 1 from baseline (essentially 0 particles got through); phase 2 increased by 18 (best of all filters at this phase); phase 3 did not increase at all (0, best of all filters) | increased from 4.07 to 6.63, the highest post-contamination pressure of any filter, framed by the narrator as evidence of the best contamination trapping |
| 6K&N$44.19 | 32 layers of oiled cotton, wire mesh integrated directly into the filter media (different design than the paper filters), 516 grams, noted as 'very oily right out of the packaging' | static pressure 1.72 in H2O (lowest/best of all filters, and lower than the no-filter control's own 0.96 baseline once considered relative to the paper filters), airspeed 57.39 mph (highest/best of all filters) | 9.3s and 9.2s, best 9.2s, the fastest time of any filter tested | phase 1 3604 (by far the worst of any filter, orders of magnitude above the others); phase 2 572; phase 3 407 | phase 1 2972 (worst of any filter, 'really struggled'); phase 2 421 (worst of any filter at this phase); phase 3 5 | increased from 1.72 to a figure captioned '2 3.79' (rendered here as '23.79'), almost certainly a caption-mangled decimal for approximately 3.79 based on the closing ranking placing K&N second-best behind EPAuto for post-contamination static pressure; kept the literal caption value and flagged rather than silently corrected |
How it was tested
- baseline (no filter) static pressure and airspeed measurement
- new-filter static pressure and airspeed measurement
- 0-60 mph acceleration test in a 2003 Chevrolet Suburban, two timed runs per filter, best time counted
- particle contamination test with a particle counter tracking 1-5 micron ('small') and 5+ micron ('large') particles across three phases: after spreading 1/2 cup of flour on the filter, after a half-second air pulse, and after one minute of continuous airflow
- static pressure change from clean to contaminated filter
- filter construction comparison (pleat count, weight, adhesive layers, wire mesh design)