If you had misfires, high performance coils could potentially help with a more complete burn. That would improve hp and fuel economy.

But you would know, because you would have misfire codes.

If it isn't misfiring, not sure how you would tell the difference with a different coil.

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2007 X3 3.0si, 6 MT, Premium, White

Retired:
2008 535i, 6 MT, M Sport, Premium, Space Grey
2003 X5 3.0 Steptronic, Premium, Titanium Silver
2002 325xi 5 MT, Steel Grey
2004 Z4 3.0 Premium, Sport, SMG, Maldives Blue