You'll never know since you didn't log your dyno runs. Going forward a good first step is to do the N55 ISO firmware and a datalog to ensure it's running properly now.
BEST PRICES GUARANTEED - New N54 Performance Line Downpipes!!
JB4 **G5** On Sale - FREE Shipping Click Me - NEW JB4(N55) & DCI's $95.00
NEW F30 N20/N55 ER Downpipes and Chargepipes - BMS OCC (On Sale)