Detroit 8v71 recommended rpm

Ah, just miss it by a couple years. Thank you all very much for the information, it certainly helps with my understanding of the engines and what should be a target speed for economy, longevity etc. I will be doing some experimenting this weekend and will post what I come up with.

Well I did some rpm to speed tests earlier this week.
1200 rpm. 8.8 knots
1400 rpm. 10 knots
1700 rpm. 12 knots
1800 rpm. 13 knots
2300 rpm. 18 knots

It was starting to get up on plane but didn't want to run for too long above 1800. Also didn't know if trim tabs worked or not but now I have confirmed they do. I have it on the hard to get bottom and hull paint done.
Bottom and props were all clean and in great shape. Will be back in the water next week and will test the speeds again.

I don't know, other then the original owner said that is how he ran it. I am knew to Detroit diesels, and learning all the time. Thank you for the information.