Yes, and it is a good idea in my opinion. I looked into this once in detail for my wooden boat. (all wooden boats are in some state of sinking).
Check out Larry Pardey's book "Cost concious cruiser". He has some good information on making your boat positively boyant.
"True, your boat will outperform mine to windward, but my boat will always outperform yours at anchor." --MedSailor