Compare the Jaguar XJ S 3.6 Coupe - [1983] vs Alfa-Romeo Giulia GT 1600 Junior Z - [1972]. 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 Jaguar XJ S 3.6 Coupe or the Alfa-Romeo Giulia GT 1600 Junior Z. We'll leave it up to you to decide which is your favourite.