My 2001 X5 with Dinan S2 (everything but the supercharger) may have less horses than a 4.8, but throttle response leaves the 4.8 behind( & 5.0 mustangs). You may have to live with the 4.8 if you are looking for 2004-2006 models. I hesitate to add much to my 2006 since I get rather good mileage as is (though a strut brace & cold air intake are on the to-do list). Good luck in your search.

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Mark _______________________________
2001 X5 4.4i topaz blue/sand Sport, complete Dinan S2 , hitch, V1, tint, BSW Stage 1, Alpine INA-W910BT
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