Actually the amount of gasoline in a barrel of oil is only about 25 gallons, the remaining 40% in made into other products - diesel, jet fuel, fuel oils, etc. Assuming that the production costs are relatively equal for all content of the barrel, the $3.14 per gallon might still be the valid starting point for your analysis. You just need more barrels for a given quantity of gasoline.
ref:
http://tonto.eia.doe.gov/dnav/pet/pet_pnp_wiup_dcu_nus_w.htm
You're on the right track, but still too high.
Crude oil is not crude oil. It comes in countless grades and qualities which determine how much gasoline can be refined from each barrel. Some are much better than others.
A good average would be about 19 gallons out of a 42 gallon barrel.
This was an amazingly accurate article issued by the AP, though. I never would have believed it.
It even accurately stated that many refineries are losing money right now, something which the majority of Americans would automatically dispute.
I loved my part of the legal field, buying and selling tankers, but what a headache for the rest of the company. I loved our captains and crew most dearly. Their stories, especially the one when we picked up the refugees (which I threw a tantrum about passing by [but they were afraid of piracy]), but they were as fond of me as I them and I said if they're pirates drop them overboard, but if they're refugees bring them to safety, and we did. It was a great job all around.