After talking to numerous bartenders at several Pat O'Brien's, this is the closest way to get a Pat O'Brien's hurricane at home. They use their own brand of 80 proof and 151 proof rum. The ratio of four ounces of rum to four ounces of mix is not in doubt. But Pat O's bartenders contradict each other on which kind of rum goes in. Some claim it is four ounces of 151. Some that it is mostly 80 proof.
Upon examining their house rum, and doing some strength testing, this is recipe is what I have come up with to get as close as possible to the Hurricane you'll get at Pat O'Brien's. The most important thing about this drink is to use cracked ice, and a lot of it. If you watch them make it at Pat O's, they're packing ice in the glass when they make a hurricane. This is because this drink needs some ice to melt to balance the intense sweetness of the mix.
Also, if you don't have a 28 ounce hurricane glass, use a glass of comparable size. You need 18 or so ounces of cracked ice floating around in this drink.
You can try higher quality rums, but I'm not sure that it's worth it. The mix covers up the rum quite a bit.