The tyres on my TT are completely shot and need replacing
I was thinking of going to 235's and 315's

I currently have TechArt Daytona rims
The offset on these wheels is rediculous (25mm) which causes the current 295's to catch when going over a bump - there is a groove cutting into the sidewalls on the rears

I know rolled arches will fix the problem with the 295's - but will it be ok with the 315's??

Also, I have completely stock suspension at present
The geometry is completely off as the front tyres are bold on the inside, but have loads of tread on the outside

What measurements should I have on my suspension? - car is a daily driver