That race will be over in a flash:

Art by the very talented Mauricio Abril

This image is playing off of a very classic DC event where Superman and the Flash raced against each other. Mauricio created this piece for a gallery show called "POPcade" whose theme was to combine video games with pop culture. Yeah, Sonic would probably lose but if you are curious if Superman or Flash would win, here's the panel from the actual DC event in Superman (Vol. 1) #199 (1967):

There have been many races since and you can read a summary of all of them at iFanboy.