Ok, I have about 4 gallons of 8% abv IIPA. I ordered a regulator 2 days ago on eBay and it says it won't be here for 2 weeks! I figured it would be more like 1 week. Anyhow, I already dry hopped it and can't let the hops sit on there too long. I need to put it in the keg and carbonate it the old fashion way. So it's about...3.8 gallons. So I'm gonna have some headspace. How much priming sugar should I use?