Question for those that have 4.3 alpha gen2

[anzomcik]

I have a crestliner 2050 sportfish (picked up last year late) with a 4.3 mercruiser. The boat is 20 foot long 8 foot beam Aluminum lets say weights2500-3000 lbs loaded (i am not sure just a guess) What prop does evey one esle run on a boat that would be similiar, I have a merc prop 21 pitch that putts my motor at 4900-5000. I am a little scared to put a 23 on, because i have had experences in the past of 2 different prop brands acting very different, in terms of rpm and performance.

So i just would like to hear what others are using to help me make a choice, i do not have the money to be buying props and hoping. I want to hit it right the first time. Thanks

 

[fuzzybob]

Re: Question for those that have 4.3 alpha gen2

The best bet would be to do a forum jump over to the prop forum. My boat is about the same wt. as yours and I have a 21P on but a 19P on the way. My WOT is less than you at 4600. Max RPM should be 4800. There are some experts on the other forum to give you a hand. Good luck

 

[anzomcik]

Re: Question for those that have 4.3 alpha gen2

I had thought about that, and i did not post there because i knew the answer i would get. 1" of pitch is 200 rpm... I really want to see what other people with similiar set ups like mine are running and my thoughts were what better spot that in the mercruiser section.

 

[fuzzybob]

Re: Question for those that have 4.3 alpha gen2

I think any info you get from other boat owners will be useless. Even tho my boat is about the same wt. size etc. my gear ratio is 1.94 yours may be different, different hull and the different prop people have different specs and on and on.My boat runs fine with the 21P but my grandkids like water sports so I need a better hole shot hence the prop change. Give the experts on the prop forum all the info they need and they can dial you right in. Good luck.

 

[180shabah]

Re: Question for those that have 4.3 alpha gen2

First if that "merc prop" is the factory black max, it is not a good design, so any comparisons to it are going to give some interesting results. What scares you about changing prop brands/pitches?

Have you looked at turning point propellers? The hustler/legacy is probably the best aluminum prop on the market. You could replace your current 21" with another 21" and be very careful with your throttle hand. OR, put the 23" on there and let the venting do it's job to help compinsate with the hole shot.

 

[anzomcik]

Re: Question for those that have 4.3 alpha gen2

180shabah That merc prop i believe is a black max, It was on it when i bought it. Reasons for me being scared is i do not want to be buying several different props to find one that will work, I do not have the money to do that. I am thankful for an honest reply, your insite will help me make an informed decision. Thank you

Fuzzybob, Even thought most of your answer was of little use to me it did let me know that you are running a 21 pitch prop (or can safely) That info is useful to me allows me to see that from the replys i get most people run 21 pitch props. So like 180shabah let me know that prop that is on it is sub par, that will fill me in that my prop would not give me a true reading on how other brands perform. I am getting this info from people that own or have owned, or spent time with 4.3s. Thanks for your reply.

 

[180shabah]

Re: Question for those that have 4.3 alpha gen2

Don't get hung up the 4.3 bit. It is irrelevent. Boat weight, hull design, gear ratio, normal load carried, and how the boat is used all go together to determine what prop is "needed",
21" prop spinning to 4900-5000 is the info needed. Along with you actual WOT speed by GPS not the dash speedo.
If you were getting 5000RPM with a normal load in the boat, then you are underpropped. If you don't use the boat for watersports, then increasing pitch to 23" is probably the best solution. Actually, it is probably the best solution either way, as you will still have your 21"er for towing.

Again I can't say enough good about the Hustler/Legacy props. Do a search on here for "Hustler", you will see I am not the only one. Hands down, it is the best value out there.

 

[nlain]

Re: Question for those that have 4.3 alpha gen2

I have a 2004 SeaRay 185 Sport, 4.3L Alpha 1 1:81 ratio, dry weight per SR site with 3.0 is 2650, 4.3L = more weight, it came with a 14X23 prop. I ordered a Turning Point Hustler 14 1/4X23 and had to change to 21P. Stock prop would give wot of 5000 the 23P TP went to 4500, 21TP I am back at 5000, all of this is with over 400lbs of people added to the boat weight. TP will swap the prop as long as it still looks new, all it will cost is freight, they did for me.

 

[Tail_Gunner]

Re: Question for those that have 4.3 alpha gen2

http://forums.iboats.com/showthread.php?t=307401

Stilletto makes a Bay pro 11 that is probably one the best props you could put on a I/O trully universal....Very high lift combined with extremely strong midrange and little if any top end loss...