okay heres the deal... i just put my mustang gt rims with 245/45ZR17 tires... great in the back, i thaught they were good in the front untill i drove..there rubbing the front fenders. i dont wanna buy new tires cuz i just baught a set whit rims in 15" and i dont really want to spend the money, i need a cheap effective solution. is there some wort of coil booster that will stop it from compressing to far?
heres what happened my second test with them, had no problem first time because i didnt hit any big bumps

 

They're rubbing because they are a full inch too tall. Get some new tires.

 

Yeah, they're called adjustable coilovers and no they're not cheap.

Tyler is right. Your tires are too tall and either 1) you get new ones in the proper sizes, or 2) you leave everything alone and the fenders will take care of themselves.