Bill, as far as I can see, and based upon what my filter minder indicates, the airflow with my BHAF as seen installed above has YET to show ANY restriction. And that SAME filter minder dropped to the 2/3 restriction mark the very FIRST steep Sierra grade I hit towing our 5er with the stock OEM filter - and that was before the considerable power mods I'm now running!
I figure my truck is about 425 HP and mid 900's torque if I go full bore with the stuff I have installed.
Could I get a few more ponies out of it without the added outer cover(s)?
Perhaps - but pretty insignificant, percentage-wise - and FAR less value to me than the added filtration they seem to be providing.
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White '02 Quad cab, NV5600, GAUGES! Comp, Walbro, DTT SS intake, Rip's 4 in. exhaust, Don M's 1.6's, DSS, Frantz oil bypass & fuel filters, Amsoil air filter, MOBILE Ham Radio-IC-706, 600 watt amp, '88 Kit 24 ft. 5er, 418 HP/978 Tq., 24 ft KIT 5er.