Compare the Jaguar XK R Coupe 4.0 V8 Supercharged - [1998] vs Mazda RX7 RZ - [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 Jaguar XK R Coupe 4.0 V8 Supercharged or the Mazda RX7 RZ. We'll leave it up to you to decide which is your favourite.