Reply
 
Thread Tools Search this Thread Display Modes
 
Old 01-05-2012, 08:46 PM   #1
Lieutenant
 
GlennW's Avatar
 
Join Date: Sep 2011
Location: Plano, Tx
Posts: 69
Default 3000 SCR owners

Out of curiosity what size props are you running? I am over propped with new SS blades but I failed to find out what they were during the survey, He only inspected them but did not make note of pitch.
I'm aware of the boats condition and situation during run, a load of fuel (100 gals+), normal gear (jackets, food, drinks, coolers etc.) and 2 skinny girls. It's due a bottom wash (been 14 months per P.O.) and about 3-4 years away from a bottom job.
I'm running Twin 5.7 EFI's and if memory serves me right I was in the low end of the spectrum @4200 r's and went thru about $800 in fuel the first 4 outings.
Just checking to see what ya'll are running so I don't have to pull it out of the water.
__________________

__________________
It's an obsession....coupled with a sickness!
GlennW is offline   Reply With Quote
Old 01-05-2012, 09:26 PM   #2
Moderator

 
Join Date: Apr 2008
Posts: 4,927
Default

The Max. RPM range for a Mercruiser 5.7 EFI should be 4800 -5200 RPM. 5000 RPM would be perfect, though if we were talking about 4700rpm, I wouldn't be taking action. How many blades on the SS props? I assume these are Alpha drives? I wouldn't worry about asking other's what they run, since it appears you are over-propped, simply determine what you need correctly with a prop calculator:

http://www.mercurymarine.com/propellers/prop-selector/
__________________

shrew is offline   Reply With Quote
Old 01-05-2012, 09:59 PM   #3
Lieutenant
 
GlennW's Avatar
 
Join Date: Sep 2011
Location: Plano, Tx
Posts: 69
Default

Thanks Shrew, I'm an avid Prop'er if you want to call it that. Been in performance boating for years and propping is an art and I concider myself an artist.
I have had many wheels lab'ed, cupped, double cupped etc and have run pretty much most of them with the Enirtia being my favorite on my last boat.
Even it off the shelf had to sent to the shop to be fine tuned.
Just really curious what others with 3000 SCR's are running so when I do pull the boat out of the water I can ask myself what the heck was the P.O. thinking. Seems like he told me they were 21", I know they are 3 blade since I can see them when trimmed up.
We stepped on about 75 or so boats before buying this one so when I close my eyes and try to remember what he said...all I see is 75 people talking to me.

The P.O. owner had the boat for 3 years but knew nothing about boats and had only put 15 hrs on it according to his paper work when he bought it.
He put new wheels on it when he purchased it since it was out of the water.
He was shocked when my surveyor fired up the generator....he did not know it had one! As I said he knew nothing about boats.
He had 3 kids under 6 years old and couldn't juggle them and boating.
G
__________________
It's an obsession....coupled with a sickness!
GlennW is offline   Reply With Quote
Old 01-06-2012, 12:15 AM   #4
Admiral
 
biggerseagar's Avatar
 
Join Date: Dec 2010
Location: central Illinois
Posts: 2,155
Default

Glenn.............Our 3000 is a 2001 with 5.0L carb with bravo 2's. I have aluminum props 21X18 3/4. Because of the high cost to buy SS IMHO I would rather spend my $$$$$ on gas and not something that will results in maybe a couple MPH difference. I do know alot of boater that have gone the SS way. Even the surveyor told me that he thought it would be a waste of money..... but to each his own.

I have plenty get up and go and with a top speed of around the middle 40's with what I have .......that works for me. If I had alpha drives I would more than likely have SS props.

Roger
biggerseagar is offline   Reply With Quote
Old 01-06-2012, 01:55 AM   #5
Lieutenant
 
GlennW's Avatar
 
Join Date: Sep 2011
Location: Plano, Tx
Posts: 69
Default

Thanks Roger!!!! Thats what I wanted to hear. I have a few more ponies than you (80) and can only hit 33-34 GPS and about 4100 rpm's so that tells me I am way over propped and most likely do not have 21's.

Or I could be dragging a tree...water is low down hear!
G
__________________
It's an obsession....coupled with a sickness!
GlennW is offline   Reply With Quote
Old 01-06-2012, 02:37 AM   #6
Admiral

 
seapuppy's Avatar
 
Join Date: Nov 2005
Location: Everett Wa
Posts: 4,681
Default

it would help to know which drives you have....usually with 5.7mpi engines..they put b3 drives on due to the hp...which means if your running at 4200rpm and that's max...and your only doing about 34mph wot....either the bottom is extremely filthy or the po has the largest props on b3 drives...which means the largest made for the b3 drive is 24" pitch....the pitch for the b3 drives are 20", 22" and 24"...that's all they can put on it....so...you either need to lower the pitch to 20 or clean the bottom off really quickly...doesn't take much gunk to slow a boat down drastically...

also check the tune of the engines.....if they aren't making hp..you won't get wot...

SP
__________________
Don't compare your life to others. You have no idea what their journey is all about.
------------------------
SSN683 Association member
Par Excellence
------------------------------
2008 Bayliner 340 - "Wild Whim"
--------------------------------------
I live in my own little world....but it's okay-they know me here!!!

Avid practitioner of the martial art: KLIK-PAO.
Tap-Rack-Bang

Anyone that sez "Size doesn't matter" has never owned a boat!
seapuppy is offline   Reply With Quote
Old 01-06-2012, 03:09 PM   #7
Captain
 
pascavone's Avatar
 
Join Date: Nov 2010
Location: Massapequa, New York, United States
Posts: 762
Default

I'm not a memeber of the the first church of prop-ology but here are a few general guide line which i've picked up:

1. the main point is to get maxium horse power in the water.
2. most engine horse power curves, show horse power declining above 4600 rpm... by design of the engine. Meaning, if your turning more then 4600 your just buring gas for little effect.
3. The boat prop and your mechincal should WOT (wide open throttle) to match your boat loading condition and use for the maxium horse power curve of the engine... 4600rpm.
4. the stock props are for general use, like the new tires on your new car. (works for pulling a skier, works for 10 fat people, works for fuel eccomy, works for top speed)
5. there are 3 version of bravo III with 3 diffrent gear ratios, 1.81:1, 2:00:1 to 2.20:1 and i think a new 2.43:1, so that also effect the prob to HP ratio, so a higher ratio and a bigger prob could really cause problems.

So, 22 degree probs v.s 24 degree probs can give you more bite in the water, and push you further at 4600, but kill you on the low end getting up on plane, or pulling a skier.
Larger diameter probs sounds like a good idea, but your increasing the load on the engine throughout the power HP curve, and most time over load the engine at the wrong RPM as designed, and result in a blown head gasket. ( Like flooring your car at every green light, maxium load to the wheels, but on a boat maxium load to the prob.... same effect).

Bigger boat with more engine with a single prob, or one engine with a bravo III, still have equal performace becasue your hauling the ice maker around and full size frig.

So, end result is, if it works don't fix it, and like those out drive "whale tails", if it worked they would install it at the factory....
pascavone is offline   Reply With Quote
Old 01-06-2012, 05:15 PM   #8
Admiral
 
biggerseagar's Avatar
 
Join Date: Dec 2010
Location: central Illinois
Posts: 2,155
Default

One trick that I have learned with our 3000 is to have the trim tabs down. That will really help you get up and on plan.

Roger
__________________

biggerseagar is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Powered by vBadvanced CMPS v3.2.3

All times are GMT. The time now is 11:10 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2020, vBulletin Solutions, Inc.