[135Pats]

Only having access to 91 pump will make it difficult to run the sport or aggressive mapping, though I don't know if you are mixing in e85 or race gas...Generally speaking, the N54 has shown to be extremely flexible and willing when it comes to tuning. It's a pretty sensitive engine and will misfire if it's at all unhappy, but in the big picture I feel it handles tuning very well. The power does get a bit more unrefined, but that's to be expected, and I don't find it unmanageable at all.