What negative affects can 20 inch wheels do to my 1998 Toyota camry?
very confusing issue. look over a search engine. just that could help!
There are NO positive effects with those 20 wagonwheels. You will not be able to use your spare if one of them has a flat either unless you invent a way to drive the car like a 3-legged dog.
if you are not changing the suspension, your new tires will have to be extremely low profile to fit in the wheel well and not rub when making a sharp turn (even with lo prof's it may still rub). 20 wheels are much heavier than the stock ones which may reduce braking performance. The extremely small tire profile you will have will make the ride much harsher. These tires will have problems with even tire wear and need to be replaced quickly (keep them rotated to extend their life).