You could possible try a 205/65 or a 215/65, it may have the same overall diameter as your factory setup. I put lager width tires with a mumerically lower aspect ratio on my 190 and the diameter was the same. The larger diameter tires may affect your accelleration slightly, but may give you better highway gas mileage.

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1990 190E 2.6
1996 Grand Voyager 3.3
1985 Mustang GT 5.0 5 SPD
1982 Suzuki GS 750T