Doc,
I can tell you from personal experience. '71 Sanger shovel nose ski hydro, maybe a little lighter than your Stevens, but not much. Pretty decent lake boat with a .060 over ex-NASCAR Hemi with alky Hilborns, ran 121 quarters at mid-10.20's around 8400 with 22% gears and I think (its been 30 years) 11 1/4 by 16 Menkens prop. For grins between rebuilds I threw a .030 over 383 together, VHS prepped 906 NASCAR heads, 540" Erson Mushroom with 850 on a Tarantula (Torker?)manifold, nothing exotic, just decent parts. Motor sounded plenty healthy on the trailer, trying to get it to leave hard was another story. Get up on a plane and it was a sweet little cruiser, just didn't have enough bottom end to get it up quickly. If you want to cruise around the lake and get decent mileage(thats a relative term in a boat), think you could have some fun with a 383. A lot of people mistakenly think a high-winding low torque setup should work in a boat if it works in a car, but that is seldom the case, especially in a direct drive boat. Water just has a way of absorbing torque and HP, and I don't understand the physics, just know from experience that it does. My