4 gal boil with BB Extract Kit - IBU question

[sudsmcgee]

I brewed my second batch ever last Friday and it was also my second extract brew. Both were Brewers Best kits that called for a 2.5 gallon boil. I used exactly 2.5 gallons on the first batch, but for this one I decided to boil 4 gallons (BB American Amber Ale). I didn't reduce the hops or perform any late extract additions. My question is: How much of an increase in IBU can I expect from this? I've read some threads on here that suggest it won't make that much of a difference because the hops are nearly maxed out at 2.5 gallons for these kits. Others say you should reduce the bittering hops and add them later for aroma. What are your thoughts?

If you were making this kit, what would you do?

BTW, I know it will taste great regardless. I'm just curious and like to learn.

Edited to link to recipe: http://www.ldcarlson.com/public catalog/Brewers Best Recipes/1007_American_Amber.pdf

 

[nanofreak]

Hard to tell, unless I missed it it doesnt even state the type of hops, let alone the alpha acids in them.

 

[sudsmcgee]

The packets did list the AA content and I wrote them down. The 1 1/4 oz of Brewers Gold bittering hops pellets were 9.7% alpha acid and the 1/2 oz of Williamette aroma hops were 4.9%.

 

[sudsmcgee]

Is this a stupid question or something?

 

[McGarnigle]

You can try a calculator like the one below. I think you might be adding ~10 IBUs.

http://www.brewersfriend.com/ibu-calculator/

 

[sudsmcgee]

Thank you. I'm a noob and didn't even know such a tool existed! This helps a lot.