No they don't raise your up. The place I got they just put the tester in the tailpipe. If you pass there is no problems. I have never had anyone look under the car or in the engine bay. Our cars have plastic on the bottom so a mirror is not going to do much.
New - 2013 - 320i - 15% Tint - Future Mods ( BMS Tune, Suspension, Wheels, Exhaust)
Sold - 2007 328i (3-Stage Manifold - BMW Perf Intake w/Scoops - Powerbox - Magnaflow Exhaust - MMW Headers - KW Street Comfort - VMR 701s 19' w/M3 offset - BMW Strut Brace - 330I Brake Conversation - 5% Tint All Around - 8K HID Fog Lights -Angel Eyes)