well, we didn't suggest anything, b/c we'd be full of shit if we did without knowing the wheel dimensions, width and offset
and for reference, spacers are a bad idea, for many reasons, not to mention, our cars require such a high positive offset they almost never make any sense (~50 for an 8" wide wheel, which is what most 19's are, if not wider).
If the wheel is wider than 8", forget it. If the wheel is 8" wide, you need at LEAST a 50mm offset to run a 225 tire, not to mention, 225/40-19 would be WAY too big. You';d want a 225/35 or 225/30-19 instead.
Stock tire diameter=25.07" Diameter of a 225/40-19=26.08"
And before you ask, if you have a 40mm offset, and add a 10mm spacer, it becomes a 30mm offset, so spacers won't help you.
If you are insistent on running 19's (which will KILL your performance, give you a ridiculous tire bill, and likely cause you to dent a rim in the near future), you want a 19x7.5" wheel with 48mm offset if you can find one, although 19x7.5's are fairly rare. If you do find one, I'd recommend a 215/35-19 tire to be sure you don't rub.
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