406oc.co.uk

the wheels on my 406 seam to be too big for the arches.

the inner arch plastic has been cracked and split from the wheels on full lock.

also knocked the drivers side front bumper corner off its mount...

the tyres fitted to the wheels are only 205, 40, 17's .... so does anyone have an idea of what could be happening?

First impression is the offset is incorrect - do you know what you have?

I'd agree there. Offset is likely to be the biggest issue. I'm running 17's with 225/45's on the front and 235/45's on the rear and have no problems like that at all, and I drive mainly on country roads through the Pennines so lots of hills and corners for them to catch on.

205's will make your speedo under read quite badly aswell as they are way too small for the 406. If the wheels are originally off a Ford, then you will need 20mm spacers and longer bolts which is what I run.