A Double IPA/ Imperial stout from a reg kit?

OK, I have been seaching, but I couldnt really find an answer.

Is it possible to make a double IPA by, just getting a regular IPA kit say from AHS and make it a 2.5 gal?

From what I gather by reading other recipies, a double IPA simple has more fermentables to get a higher ABV, and more hops.

Has anyone every tired this?

And what about like an Imperial stout? If I took a regular dry stout kit from AHS, and just made a 2.5 gal batch, would that be an Imperial stout?

ok, one last question; when I am looking through the AHS website at all the tasty kits, they say they recommend double pitching for high ABV. Now if I am using a single kit but only making a 2.5 gal, and I pitch the single tube of yeast...is that double pitching?

I got a 3 gal carboy just sitting around, so I thought I could put it to some good use.

Couple things...

A "double IPA" is not necessarily double the gravity and hops. The OG of a regular IPA could be 1.06, so if you half the water, that could be well over 1.12. That falls outside the range for "Imperial IPA". You can however do whatever you want though, and do not have to abide by style guidelines. They are however only guidelines.

Same thing goes for an Imperial Stout. Chances are pretty good that doubling a dry irish stout would not end up in something you would want to drink.

You should download beersmith or some similar brewing software that does scaling very well.

As far as pitching rates go, use the pitching rate calculator on mrmalty.com.