I stand corrected if that is the ratio...you Defo need at least a 21” then...if not a 23”.
I was wrong in thinking it might be a 1.47 with that engine and boat package. Perhaps it is because it isn’t an MPI.
No, the carbed 5.0 with a 1.62 ratio in his boat is a 19p at best. More pitch and he needs more motor
Hi Scott
There are 4.3’s with that drive in similar boats running a 21”, that I know of.
any why havent you put the boat in the water to test yet?
Your Chaparral Extended V plane hull is the same as mine and my previous Chaparral and the same as they used for the next decade on their boats. Some hulls have a 2000 patent date and and I think some have a 2002 date on them. I'm thinking you have what should be a 50mph boat loaded up. My previous Chap was a 48mph boat with a 4.3 liter 21inch prop which weighed within a hundred lbs of your model and so was a bit underpowered but was a bit newer and my current which is heavier but has a larger engine is substantially faster on top and bottom end. Maybe I could have eeked a couple more mph out of that 4.3 at the expense of the bottom end. The current boat has a lot left to give as it is propped for out of the hole. I'm curious how this all works out.
Interesting info. Which ratio do you had in your setup to turning a 21pitch with a 4.3 and goes close to 50 mph.
Actually this boat weight 3221 pds per specifications, its a heavy hull without mention 46 gal on gas. But yeah Im still curious too and cant wait to put it ln the water this weekend just to
Just to push the throttle down
Interesting info. Which ratio do you had in your setup to turning a 21pitch with a 4.3 and goes close to 50 mph.
Actually this boat weight 3221 pds per specifications, its a heavy hull without mention 46 gal on gas. But yeah Im still curious too and cant wait to put it ln the water this weekend just to
Just to push the throttle down
the 4.3's with the 1.84:1 ratio and 21p prop are actually faster than the 5.0/1.62 ratio/19p. the larger bore than the 5.0 gives it a nice looking torque curve
the 5.0 needs a 4-barrel and a slightly different cam, along with some head port work to make it shine, especially with the smaller bores.
Have you tried going out with just the prop change? Or is your testing after both things were installed, tabs and prop? Will be difficult to divine between the changes. I believe Nauticus recommends dialing the boat in for a prop first without the tabs, then go with the tabs for specific bow-rise and hole shot issues. In a lot of cases the top speed is affected by tabs and may not be able to be tuned out by changing strut pressures or tab holes.
I would try without the tabs to see what the new prop does on the boat. You can get different brackets for the tabs that allow you to move the tab up out of the water without removing them.