[maxxdude1234]

I doubt you would be able to do run 2 9L's off a single set of cells. JONNYMAXXIMA runs duel 9L, but has 28cells. Running 2 hot motors like the nemesis 9L on one set of bats is only asking for trouble...

You didn't state what you wanted to run this set-up in, you could of course try using D size cells if you have space - but 14 D cells would weigh and cost about the same as 28 sub c cells. The other option is to just go for a bigger single motor, which would probably cost less as well