Prop recommendations

The Main Sand Box for bertram31.com

Moderators: CaptPatrick, mike ohlstein, Bruce

Post Reply
J Graham
Senior Member
Posts: 49
Joined: Oct 7th, '07, 10:58

Prop recommendations

Post by J Graham »

Friend is completing a 31 project. Bahia Mar redone with reman 370 Cummins and 1.5 to 1 gears. Any thoughts on where to start.
Thanks
JG
User avatar
In Memory Walter K
Senior Member
Posts: 2912
Joined: Jun 30th, '06, 21:25
Location: East Hampton LI, NY
Contact:

Post by In Memory Walter K »

Your biggest problem will be going slow. I would recommend adding cup rather than pitch as cup works on the higher rpm end of the scale. I would start at 20X24 or 21X24 with a #2 cup. I'm sure some Bahia Mar owners will chime in. Better to be a bit underpropped than overpropped.
User avatar
bob lico
Senior Member
Posts: 5278
Joined: Jun 29th, '06, 19:22
Location: sayville,long island

Post by bob lico »

any kind of tower?
capt.bob lico
bero13010473
User avatar
Bruce
Site Admin
Posts: 3789
Joined: Jun 29th, '06, 12:04
Location: Palm Beach Gardens, Fl.

Post by Bruce »

Prop pockets?

Shaft size?
any kind of tower?
Bob, don't think it would make a difference in that application unless it was 30' tall.
User avatar
bob lico
Senior Member
Posts: 5278
Joined: Jun 29th, '06, 19:22
Location: sayville,long island

Post by bob lico »

bruce you never know " oh did i forget to tell you i have a tune tower" you know the story all to well . how about " since you worked on the boat"----------------
capt.bob lico
bero13010473
User avatar
Bob H.
Senior Member
Posts: 1279
Joined: Jul 10th, '06, 19:49
Location: Rehoboth, Mass.
Contact:

Post by Bob H. »

J Graham, I am building the same boat, 66 Bahia Mar, 370 remans, 1.5 ZF Gears, 1 3/4 shafts, oversized Pats rudders, moved all the weight aft, tank, bulkheads, engines, retabbed entire boat, massive engine beds, etc. keeping shaft angle as flat as I can...I am Listening Bob Lico...thats alot of HP for this boat but it can be done...just overbuild everthing...BH
1966 31 Bahia Mar #316-512....8 years later..Resolute is now a reality..Builder to Boater..285 hours on the clocks..enjoying every minute..how many days till spring?
User avatar
bob lico
Senior Member
Posts: 5278
Joined: Jun 29th, '06, 19:22
Location: sayville,long island

Post by bob lico »

bob h think about this ;as of 2006 the smallest twin diesel hp in a 31 sport fisherman is 380hp !!! secondly with that beauty on plane ,no tabs of course the water with just touch the bottom in line with the steering wheel then back off to low torque line of engines about 1950-2000rpm and you will be at 31mph using a ridiculous small amount of fuel .less then a single engine downeastener.
capt.bob lico
bero13010473
User avatar
bob lico
Senior Member
Posts: 5278
Joined: Jun 29th, '06, 19:22
Location: sayville,long island

Post by bob lico »

bob h when your ready brother we will rake and pitch those props on long island.
capt.bob lico
bero13010473
jspiezio
Senior Member
Posts: 882
Joined: Nov 25th, '07, 07:21
Location: Long Island, NY

Re: Prop recommendations

Post by jspiezio »

J Graham wrote:Friend is completing a 31 project. Bahia Mar redone with reman 370 Cummins and 1.5 to 1 gears. Any thoughts on where to start.
Thanks
JG
JG- is this the boat you guys were working on two years ago? That thing is going to be a monster. You and Bobh need to put signs on those boats, something like "warning secure all loose items, and hold on for dear life". Little rockets, I can't wait to hear the performance #s on these.
J Graham
Senior Member
Posts: 49
Joined: Oct 7th, '07, 10:58

Post by J Graham »

Same boat, no prop pockets, just a hard top. The Bahia Mar profile has been altered. Complete redo. Needs the right props for a sea trial,then off to the top man, then off to BVI.
User avatar
bob lico
Senior Member
Posts: 5278
Joined: Jun 29th, '06, 19:22
Location: sayville,long island

Post by bob lico »

conventional instalation with constant clean forced fresh air and fuel coolers go with michigan dyna-jet , nibral 21" diameter ,24pitch and # 5 cup .that combo will put you to the pins (3025 rpm)
capt.bob lico
bero13010473
J Graham
Senior Member
Posts: 49
Joined: Oct 7th, '07, 10:58

Post by J Graham »

Sorry, I erred on the gears. 1.23/1. Big differance.
Post Reply

Who is online

Users browsing this forum: Google [Bot] and 25 guests