Wheel offset tech question
My head is spinning over trying to purchase wheels for my car. FYI my car has the brembos, not sure that is really pertinent to this question other than it has to an extent guided what wheels I'm looking at. So, to my question. I understand that using an offset different than what the factory wheels are at (which I believe is 42 with my brembo pkg wheels) can have an effect on the car. My wheels are 9 inches wide (at least I think they are) and will replace them with a 20x9 up front and at least a 20x10 in the rear. Is there an optimum offset? Not necessarily just with respect to making them fit inside the edge of the wheel opening but to avoid adverse effects on the handling/steering of the car? I'm considering either TSW nurburgrings or Forgestar F14 wheels at the moment. With the F14's I can go to an 11" in the rear which I like. There does seem to be some debate on correct offsets. Forgestar's can be completely custom whereas TSW's are kind of a "one size fits all" where their offsets are geared towards more european cars it seems. Many of the online wheel retailers don't really seem to know the real tech on all this which is upsetting to some extent. Most of them seem to only want to be "order takers" rather than really know wheel tech. It's a pretty large purchase and I'd like to be satisfied with my first choice. Any help here would be greatly appreciated. I want the end result to look good but don't want to go for a "look" that ultimately hurts the car's handling/steering.