23 w/225 four stroke - Prop issue

gss036 · #1 06-05-2006, 01:44 AM

I would think you should be able to get 40+ with the right prop. Your speeds VS RPM seems awfully low, but I run a 2 stroker on my 23WA and get 42/43 mph trimmed out at WOT.
http://www.rbbi.com/folders/prop/propcalc.htm This will give you a prop calculator site. Maybe that will help.

schooner · #2 06-05-2006, 12:51 PM

Tried a 15.5x19 three blade this weekend. 5,500 WOT gave 36 MPH. 4,000 gave 25 mph and 3500 gave 19 mph. Numbers looking better but still a little shy of expectation. Wondering if anyone running a four stroke 200-225-250 on a 23 can share their numbers? Thanks

Briguy · #3 06-05-2006, 06:05 PM

Check with trever hicks on this board or look up his old posts.

ocuyler · #4 06-05-2006, 11:06 PM

Schooner,

Your motor should WOT at 6000 RPM with a light load, indicating that you still need another 500 RPM or roughly 2 more inches of pitch. The 21" recommendation was a good one.

schooner · #5 06-06-2006, 10:09 AM

Otto,
Thanks for the reply. Do you mean 2 inches "less" of pitch or 17" to get the revs up...? More pitch would mean less revs I think. I do see 21 inches on the Suzuki on some performance tests on 22-24 foot boats. Wondering why the Seacraft does not want the 21 pitch. Don't think that the SeaCraft is extraordinarily heavy or has a radical deadrise. I am stumped.

eggsuckindog · #6 06-06-2006, 06:22 PM

Somewhat both, they are a pretty heavy and the deadrise needs more horsepower to push. You are correct a 17" will get the RPM up, those Zuke props are funky on the sizes because of the gear ratio I think.

#7 06-06-2006, 07:52 PM

Pitch is the distance the prop would move foward in one revolution. So if you have a 21 pitch prop one rev. would push the prop 21 inches foward minus some slight slip. Changing the prop pitch is like changing the gear ratio or tire size on a car. A smaller pitch prop would traditionally be used when a better/faster holeshot is desired but should be used with caution due to the potential for over revving the motor and the larger the pitch the higher top end speeds. There as far as I know is no real science to finding the right combo. Try and find the prop that will give you a good hole shot and good topend speed without over revving go find a 21 and give it a try.

eggsuckindog · #8 06-15-2006, 10:23 AM

A single on a 23 I don't think will come close to swinging a 21, try a 17.

warthog5 · #9 06-15-2006, 05:39 PM

Those motor's are designed to run a 16in dia prop. That is what bite's the water hard to give you the holeshot.

Going to a 16in dia is going to reducer your RPM with the same pitch as the 15.5dia.

So something in 3 X 16 X 16. 17in pitch is the lowest pitch in stainless they list.
When you get it have it checked at a good prop shop that has computer redout's. I bet it will be lower than 17in pitch.

I have 2 -14 X18 prop's for my DF-140's. They checked out 16 3/4in pitch and 17in pitch. I hade them reworked to 18.5 pitch.

http://store.brownspoint.com/suzukiprops15.asp