Looking for best prop for my 2000 crownline 225BR
 

I have a 350efi at 260hp with sterndrive ratio of 1.47. At 4800 rpm i get @55 mph. Current prop is a stainless 3 blade with i believe a 24 pitch. I am new to boating so any help is much appreciated

I doubt you have a 24 pitch, probably a 21 or even 19.
With 1.47 I'm guessing a Alpha drive?

Yes alpha one gen 2. Boat is in storage will have to take a look at the prop. When i get a chance i will tell u whats written on the prop.

To determine the correct prop U must have a accurate tachometer and speed from a GPS. The boat tach may or may not be accurate, need to check it against a hand held. The boat speed-o is not good enough

Ok, took a look att my prop. It is a michigan wheel Rapture14.25" and 19 pitch

With a 19 your golden with only 6% slip at WOT

That is IF the Tach and speed are accurate

That prop is almost 20 years old. Could i get better performance from newer props or a 4 blade perhaps? I have no reason to believe the tach isnt accurate, however the speedo does move around. I have just bought a gps unit, unfortunately it is winter and boat is stored so i wont be abke to get a reading until spring on mph

First and foremost you do not know what if anything needs to be changed because your not sure if speed is correct. Not having correct information to work with, then might as well use a dart board.

There is nothing wrong with a 20 yr or 100 yr old prop so long as its within specs. To find out if its within specs take it to a prop shop and have it checked.

The prop is the device which transfers power. Every blade that is in the water creates more drag, and more drag means more power needed to turn it. Going from a 3-blade 19 to a 4-blade 17 may or may not help and can cause other issues. More blades can increases lift, more lift can reduce hull drag, but can also throw the balance off and hull can porpoise.

If you want to buy a prop, go get one and see if it works in the spring, but right now without exact info, I can offer nothing. Maybe someone else can advise where to spend money

If no other crownline peep's chime in, contact FTMBob. He played with 300 million crownline's. :)

I think AllDodge makes very good sense, with a few minor additions . Some testing with a few different propellers will help to make a target decision. Realizing what your ultimate goal is, be it speed, economy etc., will get you to the goal. We offer testing of new propellers from more than one manufacturer an easy process. Let us know if that interests you next Spring.
AllDodge, great advice. What is your back round in the marine world?

Brett

Thank you to everybody who responded

i really couldnt care less about economy, what more performance. Thank you and ill be contacting you in the spring

We'll look forward to helping anyway we can next Spring.

Brett

The all important question: what are your goals for performance?

actually the boat is under powered and with alpha outdrive, For best handling and hole shot and acceleration - the Volvo DP was best for these boats. The bottom design is not for speed nor big waters. The Bravo 3 was the next best drive on these boats with mild power.

for testing and cheap cost especially with an alpha outdrive possible the Solas brand props is where I would do some testing with. Speed wise a 3 blade prop for that hull using an alpha outdrive.

My area prob had the most 225 BR running around from 1994 thru 2002 because the largest dealer in world sold many of them. Also back in 1996 bought a new 225 cuddy with a 454 .Volvo / SX outdrive. Like I said thou the Volvo DP outdrive on the 225 handled better. Not saying top speed but everywhere else sure did.

Ok was able to get the boat out finally. GPS speed was 49. Really couldn't get up to 4800 rpm but close. @4750. Anyone have any ideas for a new prop

Contact Brett @ BBlades... if you didn't notice from his posts, its what he does! Post 10 & 14

What are your goals?

You have to define for us what you mean by "I want more performance."


You have two (2) choices.


1) Ultimate top speed (which will likely mean slower planing, and a little less efficiency (higher slip) in the midrange).


OR


2) Better holeshot and midrange cruising performance (at the expense of ultimate high speed).


Do not expect to gain anything more than perhaps, and I mean perhaps 2 mph on the top end with only a prop based on your current prop and performance. I would wager you are near the max speed in your current form. In other words don't expect a prop change to give you a 5 mph gain.


If you opt for option (1) I would play with several 3 blade props in the 19" pitch range. Laser II, perhaps a Mirage. Just gotta try a few types.


If you opt for option (2) I would try some 4 blade models with about 1" less pitch. They may be slower (by 1-3 mph) but cruise better and come out of the hole better.

Rpm question
 

My crownline has a 5.7 efi. Recently ran into a guy while boating that had an eliminator with twin 1100hp engines that he built. He told me that i could prop my engine to 5000 rpms without issue or damage. Merc says 4800, would like your collective opinions.
thanks

FYI, Brett his name was Stevie and he said he knows you and has dealt with you many times.

My opinion 200 rpm more and the GM will remain happy! done in my 350MAG for years I owned it without any failures.

A 260hp 350EFI is all out of cam at 4800. Spinning it to 5000 won't give you more speed since your hp drops off.
If top speed is your goal, go to something like a 21 pitch Mirage. The Mirage has good bow lift,, and will keep your bow high without hsving to overtrim.
Looking into a prop that has had the blades thinned will also yield better performance at the expense of suffering much greater damage if you hit anything (log, etc).
There is no free lunch.
A 21p 3 blade Mirage, with thinned blades may give you 2mph or so.

But there are other non-prop ways to get more speed. In a straight vee with no lift pad, your goal is to:
#1- Get any unnecessary weight out of the boat. Don't run a full fuel load, leave the porta potty at home.
#2- Move all weight as far to the rear as possible.. Store NOTHING under the front seats.
#3- If your boat has trim tabs, make sure they are full "up" (tabs up = bow up).
#4- Learn best drive trim angle by going up until GPS speed drops. If you don't have a handheld Garmin, etc, then load an app on your phone like Ulysse Speedometer.
Keep your boat's bottom clean.

Don't make the mistake of pouring lots of money into "performance goodies" for your boat. Your hull will be relatively happy into the mid 50's but above that, each mph costs more $ and your boat won't be within its design envelope.

When your boat no longer satisfies your speed lust, sell it and buy one that has a hull intended to, and equipped to perform at your desired speeds.

Your "water" will also steer your decision. If typical weekend traffic results in you getting beaten half to death in 22 footer, you may need to be looking at a longer deep vee, or a tunnel style boat.

But, for now, enjoy tweaking your setup to maximize what you've got.