How wide a tire can be mounted to a stock 20x9 wheel? It has 265/35-20's now, needs more don't want to change wheels

 

275 would probably be the widest to go.I had 315s but I honestly forget what wheels I had.

https://www.budnik.com/helpful-tire-info

 

WylieC, SXGT gives good information. I wouldn't go any wider tire on that nine incher. When I race at the NMRA Nationals I use my Mickey Thompson 305x19 on a 11 inch rim. On the street I am using Michelin Pilot Super Sports; 285x19 on a 10 inch rim. When I feel self destructive I use a NITTO NT05 on a 285x19 on a 10 inch rim. Hope me and SXGT helped out.