I am in the process of having some 3 piece alloys custom made for my S2000 and I am having some difficulty determining what the ideal offset would be. I have done a few searches but most of the info on this pertains to one piece alloys with a fixed range of offsets .

I am planning to use 18x8 front and 18x9 rear with 225/40s and 255/35 tires, respectively. The car will be lowered and I don't want the tyres to rub. Given these parameters I would be grateful if someone could recommend suitable offsets.

 

I would say:
18x8 +54 in front and 18x9 +62 rear.

 

Thanks That's about what I was thinking.

 

I have the same wheel set-up, but with 265/35-18 in the rear. Front has 55 and the rear at 65.