Can you lower a 91 850i series. I bought lowering springs from h&r 1.3 in front and 1.0 in back with 18 inch wheels. Does the 850 come with a self leveling system or without. Because if it does, installer told me that I cannot lower my car because it will adjust to the previous level(the factory level springs). Is this true or he just does not know what he is talking about. He said that the tires would rub??????? Thanks very much Danny C.