In about 10 days, I am going to brew a doppelbock with an OG of about 1.085. I just purchased 2 packets of Wyeast 2124 that I was going to make a starter with. I have a 2L flask and a stir plate that can handle that volume (i.e. it will not run a 5L flask) and I don't have time to brew another smaller beer and repitch the yeast.
I was on yeastcalc.com and see there is a new setting that Kai had developed. After inputting required info, it looks like I would need to step up the starter a couple times (3 2L starters to be exact, although it's a little too close to the amount...I always like a little cushion) to get to the amount of yeast I need. Funny thing is with Kai's formula, if I only use 1 pack of yeast, the end result is almost the same, about 661B cells.
Now I have time to do this, but I noticed the first starter grows the cell count to about 352B cells. Would it be possible to get a second 2L flask and do 2 separate yeast starters and combine them on brew day for a total of 700B cells instead of trying to grow up a starter with a couple other steps?
It would definitely save time, and give me a little more insurance that there is enough yeast available.