Hey I own an X5 4.4 with a sports package and my friend owns the A6 2.7T...what could win?

think the audi
how many hp does it have?

He probably has the Allroad 2.7T, am I right? For as far as I know you don't get the A6 with a 2.7T, at least not here. It has 250hp, and they both use the same time 0-100/0-62. However, the Allroad has a higher top speed. Unless you have the "Sport" version, he'll win. If you do, it'll be a tight fight :D

the x5 all the way ..

the A6 does have the 2.7T engine here in the U.S.
the x5 should have advantage if the A6 is an automatic, close call if its a manual, depends on how good the driver is