Originally Posted by The STIG
Why am I paying the most when I have the smallest engine??
Because it's a pre-2001 car. 2001 & later cars are taxed on CO2 emissions, cars made before 2001 are taxed purely on engine size, with a break at (I think) 1550cc. The emissions-based tax system has a lot more bands, which means boring (oops, cleaner!) cars pay comparatively much less then big ones.