Compare the Infiniti FX 37 3.7 V6 - [2011] vs BMW X5 4.8i V8 - [2008]. Find out which car is the fastest, most powerful, lightest or has the biggest engine in our top trumps style comparison page. Find out which car has the highest top speed or is the fastest accelerating, is it the Infiniti FX 37 3.7 V6 or the BMW X5 4.8i V8. We'll leave it up to you to decide which is your favourite.