Re: prop for maxum 1800sr
That boat look's like it has a 19 degree deep v about a 2600 lb boat, i cannot be 100% sure here but you should have a rev limiter on the boat that is set for 5000.
If so, you can be assured your tach is off, if not you need to slow her down to about 4900rpm @ wot, something to find out for sure.
Having a very similar boat and motor i could venture a guess and state a 21 pitch 3 blade for max speed or a 20 p 4 blade for top midrange and a smoother engine feel and ride.
Seeing that your going to a 5 blade i assume your shooting for midrange and pulling power, Stilletto makes a 4 blade 20 pitch ss that really woke a boat i have similar to your's. Bay Pro 11 series.
What it did was lift the boat high enough out of the water that @ wot the wake went directly out the back none on the side's, this created a lot less of wetted area and resulted in a top speed of 54 mph @ 4900 rpm
, that was a 5 mph gain over a 19 pitch alumin prop popping the rev limiter at 5000 rpm.
To get a better picture you might want to, check your tach for accuracy, post your prop's current pitch and post what gearing you have in your leg now, i assume it's a 1.66 but who knows