View Single Post
      06-27-2012, 01:20 PM   #14
Major General

Drives: 08 E90 M3, 99 E36 M3 Turbo
Join Date: Feb 2011
Location: Concord, NH

iTrader: (3)

And those gains are from (1) scoops, (2) a supposedly higher flowing but actually physically smaller filter and (3) a slightly smoother molded plastic pipe to the engine inlet. Of these, scoops are highly questionable since there is already adequate air inlet and any extra air is not rammed in, but rather follows the path of least resistance and escapes through the hood vent. Less restrictive filters probably do flow better, and bigger ones than the Afe are available as drop in filters to the stock airbox and that fit on the stock inlet pipe. That leaves the smoother molding of the Afe inlet pipe. The stock pipe is so big that I really have a hard time believing there are gains to be had here.