User blog comment:Giganta/Character Flaws/@comment-5239890-20120708234734/@comment-1038387-20120709191221

In the comics he became faster - but Barry wasn't around anymore at that time, and Wally carried his own title.

Wally is considerably slower (or, as Greg calls it: way slower. http://s8.org/gargoyles/askgreg/search.php?qid=14879].) The type of explosion seems to be the cause - lab conditions vs amateurism. I seem to recall an Ask Greg post about it, but can't find it.

Of course his speed can change later - it took two weeks after the explosion before he gained his power, so who's to say he doesn't go faster again? But, at the moment, there's no indication he's either slowed down or sped up by 2016.