Just wondering, at the moment I've got CSA Prowlers on my car, which are 16"x8" (according to the site).

What's the widest rubber I can stick on these?

And in terms of tyre pressure, if they aren't the same tyres as factory, are the inflation pressures the same or do I have to adjust?

i wouldnt go above 245s personally.. not sure what you COULD put on though

well, at the moment I have 215's, just want to go a size or two up, nothing too drastic

Go for Falken "Firenza ST-03" (silica) 225x55x16 95W .I think that U can't go wider than 225 coz main are just over alloy rim (2-4 mm).But they hold car like a glue.

Just be careful that different width, type and brands of tyre have different load ratings and with a lower than that of the manufacturers minimum load rating you "WILL" void your insurance if your involved in an accident and they notice this fact !

There has been a number of articles noting this with Rspec tyres... even though they are full race tyres and are at the extreme end of durability and any road tyre would have trouble matching them, some of those tyres have a lower load rating then the manufacturer sets as a minimum !

best advise is see a professional tyre fitter that knows what he is talking about and dont rely on people that may have no idear what they are on about !

greg