Unless you are eating a diet with protein as a significant proportion of your energy intake you don't need to bolus for protein. So unless you are on a low carb diet or a high protein diet. If you meet those conditions, bolus for protein. As suggested, start at a low value and work your way up slowly until you find a level that works. The maximum theoretical "protein ratio" is about 60% of the protein turning into carbs. Do not use this ratio, you will go hypo. It would only happen if you ate nothing but pure protein, and loads of it. I would suggest starting at 25%. Use some form of delayed bolus as protein takes a lot longer to digest than carbs - even more so if fat is also present. I use a 2 hr wave bolus (even delivery over 2 hours) but again, test and see what works for you. Maybe start with 3 or 4 hours, and tighten that up if you are going high.
Some people disregard their daily structural protein requirement before calculating a bolus for protein. This is not a bad idea. So if you are a typical adult and need around 75g protein a day for structural purposes (rebuilding tissue, etc), ignore the first 25g of protein at each meal. As a starting point - play around from there.
hope that helps matey.
