I'm running 215-65-15's on the SDL. The tie rod clearance is about 1/2 inch. If you go to the 225's, you will be quite close to the tie rod. I don't think the wheel will actually hit it, but, it might be too close for comfort.
My 1990 560SEL registers 67 1/2 MPH when I am actually traveling 65 MPH. How do I know this? I checked it with my handheld Garmin GPS and the faster you are moving the more accurate the device becomes and is sensitive to .1 MPH.
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