I bought this 2007 R56 from the previous owner who had installed Carrillo Pistons and mentioned he had gapped the rings a little bigger for more boost. He was running it with a Stage 3 Mario tune for a while. Would the excessive ring gap cause an oil slick on top of every piston and excessive oil consumption?

 

It certainly wouldn’t help! Oil coating of the pistons and valves is more a function of the crappy PCV system on the N14 engine.

 

I’m new to these cars. Would that explain the excessive amount of smoke coming out of the oil fill hole when I remove the cap?

I’ve worked on a lot of cars, built a high horsepower engine, and I’ve never seen the amount of smoke come out of the oil fill hole like this car.

 

The smoke sounds like a symptom of the larger ring gap, which would cause more blow by, and thus smoke in the crankcase