Looking at the Spec 1 SP-4 wheels for my 2006 R52 JCW. The size is 7x7.5 ET 38. Also looking to do Megan Racing Coilovers. Should I have a fitment issue with the stock 205/45r17 tires? Or possibly 215/40r17? Rubbing should not be an issue. Just concerned about the tires sticking out past the fender trim.

Thanks, Jim

 

Using 17x7.5 et 38 vs OEM 17x7 et48: The new wheels will be 3.6mm further away from the inner suspension and poke out 16.4mm more.

That's a fair amount of poke so it will look a bit wide, just imagine your OEM wheels with 16mm poke.

205/45-17 are fine for 7.5" wide rim. 215/40-17 has limited tire selection more on the aggressive side (competition tires). 40 series sidewall can be firm riding and stiff, tire diameter is small so less ground clearance.

 

Well the diameter difference between the stock 205/45r17 and the 215/40r17 tires (according to Pirelli PZero Nero spec sheet) is 24.2" vs 23.9". However the measured rim widths are 7" for stock and 7.5" for the 40 series. So if you put the stock on the 7.5" rim, that .3" difference will be even less. Going to take some measurements this evening to get a better idea.

 

Problem is not so much tire diameter, 215/40-17 gives you very limited selection of tires, which tire were you considering, mostly Ultra High Summer or Extreme Summer tires available. Depending on which tire, 40 series sidewall might be stiff riding, not suitable for bad roads.

 

Actually shifted gears slightly. Found NM engineering 18" wheels that are really nice looking. They are specifically made for the mini and even re-use the stock center caps. Tire size would be 215/40r18. Both Michelin and Continental make quality tires in that size.