No doubt Doug will be able to figure it out in no time. If it gets the best of you guys, here is a problem I had a couple years ago: A bad batch of gas that had DIESEL in it. Same thing: Started up with a puff of black smoke which disappeared shortly thereafter. Left black spots too. The dealer couldn't figure it out when it was in, but then called me the next day and asked where I got my last fill up - they got more cars in that bought that same bad gas. Drained the tank, replaced the fuel filter and all was well again (this was not in the Viper thankfully).
Hopefully yours is not so strange, but figured I would throw it out there in case you still have troubles...