Dinan has an ECU upgrade for the M5/M6 that was released boasting 628hp and 400+tq. Would be nice if they can boast the same gains for the M3 up 25%....
I would always go with the dealer install (even though it's at a price). As long as the dealer does it, the warranty is still good. Even if it is a Dinan matched warranty. I mean, where else do you bring your car when it has a problem? The dealership!
CURRENTLY: 2014 MB E63AMG-S, CF package loaded, Weistec 725hp ECU on order, Dado downpipes; 2014 BMW X5 50i ||| FORMERLY: 2008 E60 M5 ||| 2011 X5 50i, ECU upgrade to 485hp, LOADED ||| 2009 BMW 335xi, jb4 map5, downpipes, spings, etc. |||