Lifted from another board I frequent, below you'll find the cold oil pressure drops of various filters. Hot oil tests are pending.
One thing to consider is that the less pressure drop, the more flow and perhaps less filtering efficiency. What's the right balance of flow versus effeciency? I don't know. Is K&N better than Mobil 1? At flow perhaps but at filtering, perhaps not.
Brand: Pre-filter pressure, post-filter pressure, % drop
Amsoil: 40 vs 34 = -15%
Mobil 1: 40 vs 30 = -25%
K&N: 42 vs 36 = -14.5%
Fram: 40 vs 38 = -9.5%
Bosch: 40 vs 30 = -25%
Napa Silver: 38 vs 32 = -15.7%
Fram TG: 40 vs 22 = -30%
Napa Gold: 40 vs 32 = -20%
Pure1 40 vs 28 = -30%
Purolator+ : 40 vs 32 = -20%
Motorcraft: 40 vs 24 = -40%
STP: 40 vs 34 = -15%
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