i think sixto has hit it on the head. pull a front wheel and see what is marked on the rim. 23 - 25mm is what should be on the wheel. anything else may push it into the outer lip or the inner liner.
even with h&r sport springs you should be able to get 18x8.5 on there.
don't know if your replaced self leveling set up could have lowered your body too much.
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