Strange, I downloaded a very similar mod somewhere (don't remember). Anyway, why did you change other things and not just the tyres? Do some of the other changes affect performance in any way? What I need is a perfectly standard F2004 with tyres that are the same compound and dimensions as the original F2004 tyres but have no grooves. I want to see the lap time benefit of slicks vs. grooved. Does your mod meet those requirements? Thanks