juggernaut1
Well-Known Member
- Apr 19, 2015
- 1,152
- Boat Info
- Boatless - sold Searay 38 Sundancer
- Engines
- 8.1’s
I'm considering the idea of upgrading the props on my 38 to Veems (as they are local) and have the following questions if anyone is able to assist:
The 2006 Sea Ray parts list for my boat shows the following - is this suggesting that there is a different pitch for left and right props? If so, why?
PROP, 21"X 22.5"X 4.85"X 1.5" R4BC NIBRAL MIK
(TVD-8.1 S HORIZON (T-370 PHP) MCM INBOARDS)
(TVD-8.1 S HO (T-420 PHP) MCM V-DR. INBOARDS)
PROP, 21"X 23"X 4.85"X 1.5" L4BC NIBRAL MIKAD
(TVD-8.1 S HORIZON (T-370 PHP) MCM INBOARDS)
(TVD-8.1 S HO (T-420 PHP) MCM V-DR. INBOARDS
What is the clearance from shaft to hull for my boat (yes I could dive overboard - but the boat is not local)? Veem works on a clearance of 12 to 15% to determine max prop size.
What is the shaft taper for my boat - does Sea Ray have a standard?
What WOT rpm should I be seeking to achieve - 4600 rpm? When I ran the boat a few weeks ago at WOT in the open ocean with all our gear on board (we live on it on the weekends), 9ft6" dingy on front deck/half fuel/full water it turned circa 4,716 rpm (port)/ 4,666 rpm (starboard) at 29.5 knots per the smartcraft. I note that Boattest achieved 4,750 at 30.2 knots when this boat was originally tested.
At what rpm does the 8.1S Horizon develop peak HP.
Can anyone link to a dyno for this motor?
Has anyone had experience with 5 blade props as this is what the Veem on-line prop selector is suggesting for a "desired" speed of 30 knots at 4,600 rpm. Plugging in a "desired" speed of 32 knots at 4,600 rpm, it suggests a 4 blade. Note that these recommendations are subject to verification by a naval architect at Veem.
Any other comments/considerations I should take into account?
The 2006 Sea Ray parts list for my boat shows the following - is this suggesting that there is a different pitch for left and right props? If so, why?
PROP, 21"X 22.5"X 4.85"X 1.5" R4BC NIBRAL MIK
(TVD-8.1 S HORIZON (T-370 PHP) MCM INBOARDS)
(TVD-8.1 S HO (T-420 PHP) MCM V-DR. INBOARDS)
PROP, 21"X 23"X 4.85"X 1.5" L4BC NIBRAL MIKAD
(TVD-8.1 S HORIZON (T-370 PHP) MCM INBOARDS)
(TVD-8.1 S HO (T-420 PHP) MCM V-DR. INBOARDS
What is the clearance from shaft to hull for my boat (yes I could dive overboard - but the boat is not local)? Veem works on a clearance of 12 to 15% to determine max prop size.
What is the shaft taper for my boat - does Sea Ray have a standard?
What WOT rpm should I be seeking to achieve - 4600 rpm? When I ran the boat a few weeks ago at WOT in the open ocean with all our gear on board (we live on it on the weekends), 9ft6" dingy on front deck/half fuel/full water it turned circa 4,716 rpm (port)/ 4,666 rpm (starboard) at 29.5 knots per the smartcraft. I note that Boattest achieved 4,750 at 30.2 knots when this boat was originally tested.
At what rpm does the 8.1S Horizon develop peak HP.
Can anyone link to a dyno for this motor?
Has anyone had experience with 5 blade props as this is what the Veem on-line prop selector is suggesting for a "desired" speed of 30 knots at 4,600 rpm. Plugging in a "desired" speed of 32 knots at 4,600 rpm, it suggests a 4 blade. Note that these recommendations are subject to verification by a naval architect at Veem.
Any other comments/considerations I should take into account?
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