[jspatz1]

My honest advice is to stick with chains, but that is another story....

As to your question about enough belt wrap on the center pulley, I would have to say no, not enough. Remember you are trying to transmit all the power to both end axles from this wrap. With less than 90 degrees of wrap, you are asking for slippage. The high tension needed to keep this from slipping will add drag from the idlers, and the low number of engaged teeth will be hard on the belt. It is always difficult to try to drive from the center of a belt or chain path. You might go with just one idler, and bring it around to create much more wrap on the center pulley. Is there any reason you do not want to use to use two belts? This only involves one additional pulley, eliminates the idlers, and as already mentioned it prevents a fully dead side.

Another option would be to use a double sided belt, and take the belt through an "S" shape in the center with two driven pulleys, no idlers. This would require an output shaft arrangment with two driven shafts turning in opposite directions, which would be easy to do with a gear pair.