[Ginola]

245/40/18 fit on mine, I have literally a fag paper gap between the coilover and tyre on the fronts, although my offset on those particular rims is quite different to yours being ET55 and 8.5j

If you want I could lend you a pair of Dunlop 245/40/18 tyres from the shed for you to try? *test fit one* don't drive anywhere on a non matched set of tyres!

I have a pair of eagle F1's and a pair of Dunlop sports in that size.. I removed from my current track wheels before fitting 888's (Neither brand rubbed on front or back)
I will be re-using the EagleF1 245/40/18's when the current 225s reach end of life or I might be persuaded to part with them for the right money, (they are pretty much brand new have covered a couple of hundred miles)

Also have some 225/40/18 eagle F1's sat in the shed with a couple of mm tread left if they are of any use to anyone.