With any naturally asperated engine.... letting it get more air.. and letting it blow that used air out... is vital to a little more performance... I'm not sure if Jim Conforti has created a chip for a X5 or not.. but you could possible go to one of his big distributers... ( turnermotorsports.com ) and email them... Or if you dont want to go and do that.. you could PM me ... and I could give you the email of someone that might know. Either way.. you will probably get a responce in a week or so. Or you may just want to call... that would be the fastest. I would do some searches on google.com for some power upgrades for a X5... after all.. its just another engine ... just set in a different engine compartment.. with a little different suspension... good luck. Hope this helped some.
1997 E36 M3 1990 E30 325i