This is a question i should really know the answer to :D but how do i decide on how many bluff combos i want in my 4bet range?

Lets say im 4betting AA/KK 100% QQ 80%, and then AK combos at a frequency that rounds my total combos out to around 27 combos, how many bluffs do i want to have?

I presume sizing has an impact, so lets just say for example i raise 2.5bb, v 3bets 8bb, and my 4b sizing will be 22bb.