I've owned both the 1.8 (Z18) and the 2.2 albeit in Vectras not Astras and the 2.2 is a fair bit quicker than the 1.8, although I do find I use quite a lot more petrol with the 2.2 than I did in the 1.8. I do have a heavy right foot a lot of the time though lol. Don't get me wrong, the 1.8 was a...