the OD-2 doesn't excel in crunch settings, if i understand you correctly. for that to be achieved, you need a Blues Driver type to actually enhance a single coil voicing then it'll be a potent formula.
put your pickup switch to the mid position, back off you guitar volume to taste & try the Blues Driver to hear this in action.
also, check out the pedals listed by Cow, above. if there is any need in intensity but nothing metal-grade, consider MI Audio's Crunch Box 8)