Compare the Pontiac Firebird 6.6L Trans Am - [1979] vs Citroen Xsara 2.0 16V VTS - [1998]. 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 Pontiac Firebird 6.6L Trans Am or the Citroen Xsara 2.0 16V VTS. We'll leave it up to you to decide which is your favourite.