Well, I brewed up another version of the 4.0 for my 30th birthday party to put on tap in 10 days. I subbed the Pearl for a 50/50 mix of two row and golden promise, as was suggested here before, and I significantly upped (and slightly changed) the dry hop. I just added my first of two charges today with my new stainless dry hopper in my corny and purged with co2. First addition was 2 oz Simcoe, 1 oz CTZ, 1 oz Amarillo, 1 oz Centennial, 0.5 oz Apollo. Second addition will be in about 4 days and will be 1 oz Simcoe, 1 oz CTZ, 1 oz Citra, 0.5 oz Apollo. Should give me more than enough time to force carb at 20-30 psi before the party. The beer came in at 7.8% and was damn tasty and aromatic before any dry hopping.
If you got the pH and hardness right, you should end up with something better than Heady...your friends will be impressed. Anyway, it's possible I was reading the 4.0 recipe wrong with the amount of hops, and 5.5 oz is the total, but until the OP or someone who knows what he did for the 4.0 recipe verifies, we'll never be sure. Anyway, a beer with 9 oz total for dry hops will definitely get your party started, and the second dry hop will make it a bit different from Heady so it will be your own thing.