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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

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.

any kind of tower?

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.

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"----------------

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

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.

bob h when your ready brother we will rake and pitch those props on long island.

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.

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.

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)

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