What size rims can you put on your 1994 G20 conversion van 18 or 20 someone told me is the biggest.?

The largest rim size that can typically fit on a 1994 G20 conversion van is 17 inches, but this may vary depending on the specific model and modifications that have been made. It's always a good idea to consult a professional or reputable source for accurate and customized fitment advice for your specific van.