Prop question

[Captdj]

Have a 2001 23 SeaCraft and repowered with a 300 Suzuki (30 inch shaft no bracket) recently and looking to see if anyone has run the 16X20 with that set up?

I have asked and looked on other post here and THT and everyone seems to be turning the 16X18.5, but was curious if anyone has tried the 20 and what there numbers are.

The shop put the wrong prop on and gave me a 16X17. I noticed it too late, but they are making good and when they come to swap the gauge they are bringing the 18.5 that I asked for. The 17 is like a raped ape coming out of the hole shot, but I want a faster cruise and know I will pick up just a little with the 18.5 so was wondering about the 20.

Current numbers as of 2 days ago with 4 adults and 2 teenagers fuel of fuel no fishing gear were.
WOT- 6300-6400 46 MPH on GPS (RPMS mights hve been a touch higher but wasn't able to constant stare at them)
Cruise- 4600 31-33 MPH
4500 30-31 MPH
4400 29-30 MPH
Didn't pay attention to anything lower. I came from a 300 HPDI and i know I won't get those cruise numbers back of 40 MPH at 4000, but I enjoy the MPG savings of the new motor just would like to cruise a little faster.

[kmoose]

18.5 is what you want. I have both the 20 and 18.5. If it is a CC with a bracket you might be ok with the 20 but for a Tsunami/Scepter the 18.5 is perfect.

[Captdj]

It is a 2001 CC

[bigtahuna]

Captdj
What height is your motor mounted? I wasn't able to run a 18.5 to full wot on mine. I'm thinking mine may be mounted too low in the center mounting hole.
Thanks Dave

[Captdj]

Originally Posted by bigtahuna

Captdj
What height is your motor mounted? I wasn't able to run a 18.5 to full wot on mine. I'm thinking mine may be mounted too low in the center mounting hole.
Thanks Dave

I'll have take a look tomorrow when I run down to swap out props. You should be able to swing the 18.5 from everything I have ready most guys are running the 18.5. I was wondering if I could go up to the 20. Going to try out the 18 for a little and see where my numbers are and make the call if I want to switch to the 20.

[Captdj]

Looked today when I was down putting the 18.5 on and the motor is mounted 2nd hole from the top. Motor is mounted straight to the transom no bracket, spacer, or JP

[bigtahuna]

Mine is on the transom also. So that would mean yours is mounted lower than mine. Do you have bottom paint? Does your boat have a raw water intake mounted on the starboard side of the keel? Sorry for all the questions. Thanks.

[Captdj]

Originally Posted by bigtahuna

Mine is on the transom also. So that would mean yours is mounted lower than mine. Do you have bottom paint? Does your boat have a raw water intake mounted on the starboard side of the keel? Sorry for all the questions. Thanks.

I have bottom paint. I have two thru hull pick ups. One starboard and one port. Port is livewell pick up and starboard is saltwater washdown. Have a thru hull ducer installed on the port side side also. Haven't messed with motor high at this point. Just switched to the 18.5 and haven't had a chance to run it and get numbers. I have looked over the back when running with motor trimmed and is seems to be at the hight. I'm sure I could go up one hole, but didn't want to haul and messing with it right now.

[Captdj]

Ok so I switched the prop over to the 18.5 my cruise speed came up like I was hoping. Now I am wondering if I should raise the motor 1 hole. Right now it is mounted one hole down from the top (next hole would mount it as low as possible).
Crusie- 35mph at 4300-4400.
WOT - 44mph at 5800
This is with 2 adults and fuel of fuel, t top, and full curtains.

Switching from the 17 to the 18.5 I gained crusie speed and I am around where I want to be, but I lost on the top end. Knew the RPMS were going to drop, but didn't expect to go from 6300-6400 to 5700-5800. Now I am wondering if the motor shouldn't go up 1 or 2 holes.

Boat again is a 2001 Seacraft with a 300 zuk mounted to transom no JP or bracket 30 inch shaft