Centennial IPA

This is one of the best all-grain IPA recipes you can use.  Magnum as the primary bittering hop gives a soft bitterness that won't overpower, even with the high IBUs.  The Centennial is the star here, providing a dominant grapefruit flavor that works well with the light malts.  

Grain - 
15 lbs 2row
1lb Munich 20SRM
1.5lb crystal 20

Hops - 
1oz Magnum 60 mins
1oz centennial 30mins
1oz centennial 15 mins
1oz centennial 10 mins
2oz centennial 5 mins
1oz centennial 1 min

Yeast - 
Safale US-05 or Wyeast 1056

Assume 70% efficiency with this recipe and you will end up with an ABV% right in the middle of the target for an IIPA, 8.7%.  

You can download the Beersmith Recipe File.  This is a great way to put in the exact alpha acid % for your hops, and tweak the recipe for the efficiency of your system.