1988 230we propeller sizing help!

[230weekenderUSC]

Hey all, thanks for any help you can give!

My 1988 230 weekender has a 2003 efi 5.0 and alpha I gen II. I'm currently running a 3-blade Mercury black max cupped 16x16 aluminum prop. I top out around 34-36mph at 4400-4500rpm. It takes about 5 seconds to get on plane with light load and no tabs. With 6 on board, it takes 10sec+ and full tab, but once on plane she runs just fine. I am mostly interested in mid-range economy, and currently cruise around 28-30mph at 3100-3250rpm which I am happy with. BUT I would really like a better time to plane. I'm thinking about a 4blade SS prop. Another CSR member is selling a 14.125x17 4blade SS Hill marine prop. Does this sound ok to go up in pitch with the decrease in diameter? I can fit a 16" diameter at the biggest. Sea Ray sells my boat with a 14.5x17 and says max rpm is 4600.

What is the best prop for my boat??

 

[chasemixon]

I'm no expert on props, but I will say anytime I increased the pitch of my prop, say I went from a 17 pitch to a 19 pitch my time to plane went up, but I went faster with less RPMs. I may be totally wrong on this but that was my experience, and I only had 3 blades on both... so going to a four blade may help with that... when I decreased the pitch time to plane went down... but RPMs went up to keep the same speed.

 

[230weekenderUSC]

I'm no expert on props, but I will say anytime I increased the pitch of my prop, say I went from a 17 pitch to a 19 pitch my time to plane went up, but I went faster with less RPMs. I may be totally wrong on this but that was my experience, and I only had 3 blades on both... so going to a four blade may help with that... when I decreased the pitch time to plane went down... but RPMs went up to keep the same speed.

I'm aware that going up in pitch leads to higher top speed and slower time to plane, but I didn't know if the decrease in diameter would make up for the increase in pitch? Sounds like maybe that isn't the prop for me, but what can I do (as far as propping goes) to help my planing time and slow speed planing, while maintaining economy

 

[chasemixon]

Sorry I didn't read that correct first time, I would not imagine the decrease in diameter would do much, but if it were me I would want it to be the max size the 16.. more water you can move the better!

 

[230weekenderUSC]

16" diameter is hard to find

I should mention that my planing difficulties arise from the engine lugging and not being able to build rpm's. I'm thinking about a quicksilver black diamond 4-blade 15x16... experts?

 

[rexcramer]

Try a 3 blade Mirage Plus prop with a 15" pitch. I have this same prop on my Sundancer and it is designed for heavy boats and has large diameter blades to carry heavy loads. Also you can find them used easily, I found mine on craigslist for $125.

 

[230weekenderUSC]

Try a 3 blade Mirage Plus prop with a 15" pitch. I have this same prop on my Sundancer and it is designed for heavy boats and has large diameter blades to carry heavy loads. Also you can find them used easily, I found mine on craigslist for $125.

Thanks for the suggestion, I ordered a cheap solas alpha 4 blade 14.8x15 to try out. I'll report back with results in a couple weeks.

 

[dvx216]

My 230 has a 5.7 260 hp so it's a little different but I'm running a 14.5"x 17" . With boat fully loaded two adults one small dog the hole shot is good comes right to plane with carbed motor. This is done with drive full down and then pulling drive up through the rise of rpm. With this set up my motor has never lugged even if you go WOT from a dead stop.WOT with this prop rpm is 4600 at 42 mph if I remember correctly. The combination of pulling the drive up as the boat rpm rises helps reduce drag to come to a plane at no point do I get to WOT before I'm backing out of the throttle and easing into plane.

 

[Lazy Daze]

You have an EFI, not an MPI engine, right? Top RPM is 4,800 - not 4,600. It should say on the flame arrestor cover.

 

[230weekenderUSC]

Yep I'm running efi. You are correct on max rpm. Sounds like I am currently over propped. I need WOT to get on plane with anything mor than 4 people on board.

 

[Lazy Daze]

At 4,500 RPM's you're not horribly overpropped. You're in the "range". But I usually like to prop a boat for the way I'm going to use it most of the time - with a load, not just one or two people. For those "light" times, I can control the RPM with throttle. Now, the downside to going to a smaller (less pitch) prop is going to be an increase of cruising RPM's. Depending on how far down you go, you could lose top end, too.

When it all boils down, 6 people and gear is a lot of weight for a heavy (big) 23' boat with a 27-year old hull design. There's only so much you can do or expect out of it. After first re-propping to an appropriate prop, another option would be to increase the size of your tabs.

You can also try moving/storing more weight further forward, as opposed to aft. Even adding dead weight to your bow is an option.