Buckhead Imports Performance E39 M5 goes 11.68 at 122.4 MPH in the 1/4 mile with their RMS Supercharged E39 M5.
Buckhead Imports and RMS still hold the world record for fastest 1/4 mile time in an E39 M5. The record run was set back in September 2012 and has yet to be broken. This mean M5 is equiped with an RMS stage 2 supercharger kit making 575 whp on stock engine internals! Since this run the Buckhead Imports M5 has been upgraded to an RMS V7 Ysi system with a custom low compression engine and is currently making around 700 whp.