I have trawelled using search thorugh all the posts about which grade petrol to use. I am picking up an MY98 AUTO sportwagon tomorrow and I know that it is going to have an empty tank. When I get to the petrol station what do I need to put in it?

NUL or SUL?

Which gives best MPG, and which will give the most power/smoothness?

Will optimax have any effect? You have mentioned that it contains cleaning aditives, whould that benifit the engine?

I am only intrested in the relavance to a sport, not a turbo, and it is a uk car not an import.

Let me know?:)

In general the only advantage of filling up with higher octane fuel in a NA car is that the timing can be advanced. Check the manual for the minimum spec, don't think there's much advantage in going for higher octane.