M5 Expert (>4000)
Join Date: Feb 2007
Location: San Jose, CA
Thanked 565 Times in 475 Posts
Didn't know they had these. I remember one member doing some tests on his car by covering the secondary hole and I think it did show some gains.
At $20, it seems like a non-issue but would love to get more feedback from anyone who's done it.
2006 M5 Blk/Blk/Alum Fully Loaded
Engine: ESS/RPI Stage 2 Tune | RPI Ceramic Coated Headers + GTS Exhaust w/Gloss Black Tips and Red RPI Logo + Ram Air Scoops + BMC Filters + Block-Off Plates + Pulley + Oil Cooler | Sprint Booster V2 | Euro SMG LC Tune
Wheels, Susp & Brakes: Neez QD7s Hyper Black 20x9-10 | PS2s | KW V3s | Dinan FRC + Rear Sway Bar + Front & Rear CF Strut Braces | Brembo 380mm BBKs
Exterior: Hartge Splitter & Diffuser | Vorsteiner CF Trunk Spoiler| Republic Wraps Side Diffusers | CF Lower Mirror Covers | CF Side Gills
Interior: RDSport Alum Pedals | Hardwired V1 | iPod Integration Kit | BSW Stage 1 Speakers | Earthquakes SWS Subs w/HiFonics Zeus 500W Amp | Flat Bottom Steering Wheel w/CF Trim | AS Designs Red Tachometer
Lighting: Eurospec Headlights w/Clear Corners | LCI LED Taillights | MTEC V3 AEs | Trinity Autosport Interior LEDs | F10 Style Smoked LED Side Markers
Coded Options: Folding Side Mirrors, Windows and Moonroof w/Remote | Deleted "Accept" Screen | Turn Signals in HUD | Real Speed in OBC Screen | Automatic Heated Seats Controls in iDrive