I purchased the S-flow twice and found grime, dirt, dust, sand, buildup on the inside of the tubing and y-pipe. Now I run either paper, AFE or K&N.
ASP CUstom Tuned Stage 3 Featuring Virgin K04's
Ported 2.7 Heads w/ Match Ported 01.5+ Manifold
MTM Headgaskets
RS4 Cams
034 Fuel Pump
RS4 Y-pipe
DUH FMIC & Oil Cooler
DUH / Labree Split DP's & Dual 2.5'' Exhaust
Forge DVR
RS4 MM & TM
Vogtland GT's
ECS Stage 4 / 6 Piston Cross Drilled / Slotted, Stasis 298mm
358 Dyno Dynamics Wheel HP on 91, 420 Wheel on 109.