I have a 1996 16' double eagle with a 1996 Johnson 60hp(commercial motor with the bigger leg). My boat had foam under the floor when I installed a gas tank but it was bone dry underneath. With the 60hp the boat tops out at 35mph. Hole shot with 2 guys and fishing gear (17p prop) is great. Anymore than 2 in the boat I need the 15p prop. Will be upgrading to a 115hp soon(max hull rating) 70hp is way too small for a 17'