Bertram31.com General Bulletin Board

PROP QUESTION 31

Posted By: bob fioresi
Date: Saturday, 23 July 2005, at 10:07 p.m.

I have a 31 express 1962 with a marlin tower. 440 chryslers. Took off 17x18 because port was max at 3100 rpm starboard was 3600 rpm. Props were a little funny so was told by the prop man that 17x15 would increase rpm which it did but speed @2950 went from 25 mph to 21. rpm now max out at 3600 port and 3700 starboard.Thinking of trying 18x17. to incrase sprrd. Anyone have a 31 like mine with any ideas or can tell me what they are doing and using My documantation says it weighs 9 tons. Appreciate any help as i plan on changing props on wed. Thanx