New Found RPMs

[JGKoenig]

For a while now I have been complaining about the lack of RPMs (was getting 4100-4300 RPMs with just me) on my 1983 Chrysler 140. I have it on a 18.5 foot Renken Bow Rider. I tried everything. I finally dropped down from a 19 pitch cupped prop (3 fin) to a 15 pitch 4 fin Composit Prop. I am now doing right at 5000 RPMs . It is cruising around 35MPH. Does this sound like the correct speed? Is 5000 RPMs OK or do I need to be going for 5500? The motor sounds awesome!!It is a fairly fresh rebuild with great compression in all cylinders.

 

[JGKoenig]

Re: New Found RPMs

anyone?

 

[rickdb1boat]

Re: New Found RPMs

Sounds like you are real close. A 13" may be just perfect, but as I said, you are real close now. Depends on whether you want to fool with it anymore or are satisfied with the way it is. RPM's are in the range now...Personally, I would be happy with it the way it is...

 

[JGKoenig]

Re: New Found RPMs

Thanks for the reply Rick. I am pretty happy with the way it is running and will probably leave it alone. If I see a 15 pitch 3 fin prop (or maybe even a 13) on Ebay I may pick it up. Kind of fun to see what each config does to the RPMs and speed. The prop I have on it now is a 4 fin.