When tuners usually change the stock ECU map a car comes with as stock, they change the parameters at which the engine works, forcing it to produce more power and torque. However, doing something like ...

I was about to call this $98,000 2018 BMW M550i with Dinan's Stage 1 tune a "sleeper", but the quartet of fatty exhaust pipes and 20-inch Forgeline wheels will definitely wake you up. It's a lot more ...