I can tell you one thing, when the LT1 in my 96Z28 engine blew due to the ATI procharger, the K&N valve cover filter supplied with the kit smoked like a freight train. I would have never known of a problem if the filter wasn't installed. Not sure of the purpose, but ATI did ship the filter with my blower kit.

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99 Lightning, JL Ram Air, Daiblo Chip(JL Programmed)and 90mm MAF,JL Power Cooler, Level 10 shift kit,PSP Lower pulley, Single Blade T/B, Bassani exhaust, . 12.42 at 109.6..Full trim and stock convertor, MT Street ET's.
New times w/ JL converter coming soon!