I wouldnt say its underpowered but it would depend on the prop and gearing of the I/O. Could get enough speed and hole shot if it all matches. I myself would take a ride if you could and see and listen for yourself. My personal boat is 22ft cuddy with a Mercr. 350cid ,260hp and is just right. The 4.3 may be good on fuel if you dont push it hard. Every boat has its own personality.