I guess when you're saying it has standard 4x4 brakes it is a Cosworth 4x4?

I have 17x8 ET35 wheels on my 4x4 Sapph with 215/40 tyres, but the front and rear arches have been rolled. I think if you use a 205/40-17 tyre the dimensions are very much the same as the standard 205/50-15, so shouldn't be a problem. But I think 215/40-17 should also not be a problem on standard arches.