First, Harley's conclusion that Dinan builds products that feel 100 percent BMW-spec is absolutely true. And second, Steve and the gang haven't just created a tuned M5, they've built a better one.

Autoblog senior editor Damon Lavrinc is in Monterey with BMW, where he has been able to confirm that the 5 Series will receive a diesel model tuned by the automaker's M performance division.

a unit that produces 616bhp and 553lb ft of torque in M5 Competition form. This clearly wasn’t enough for G-Power or its customers, so the tuner has applied both software and hardware changes to ...