50 Merc for 1980 Hewescraft River Runner?

[JonnyRingo]

I bought a 1980 Hewescraft River Runner and it came with an older broke 65 Johnson w/ a prop. I have a chance to pick up a strong running older 50hp Merc w/ a fresh rebuilt pump (50/35). I ripped all the back to back seats out and with the boat being pretty thin riveted aluminum its really light. I'm wondering if this will be enough HP for getting on plane and going up the and down the river with 2 people. I was hoping for any advice or suggestions/experience with an older River Runner. Thanks

 

[handyandy]

on a light riveted boat it will probably be fine, won't be a speed demon, but if your mostly going to be running with just two guys it will do ok. A 60/40 utilizing a 6 7/8" impeller would be more ideal though. What size is the hull that has a lot do with it as well flat bottom semi v?

 

[BigTerp]

I have a '94 Johnson 50/35 on a riveted mod-v 1648. Pretty thin hull and overall a light boat. Before I beat the crap out of the bottom, I was getting high 20's down river and mid 20's up river with 2 guys and fishing gear.