The 10.4" clutch helps with letting the clutch shift out more 'cause the belt is not having to pull around a smaller diameter. I believe where the real advantage lies is with the RK Tek Helix and torsion set-up. This clutch was actually on an '05 M7. the stock M7 clutch is only a 10" and probably has the compression spring set-up. You will need to run the ---046 belt with the larger clutch but will notice a huge difference in the over all shifting. I have a 2010 HCR and the RK Tek Kit is the first thing I will be adding to it. The 2010 helixes are different 'cause of reverse or I'd be keeping this clutch.