4.3 Mercruser 1:81 Gear 190 HP

[Ken Stephens]

Mercruser 190 hp tks 1 81 gear turning 14 x 3/4 at (4800 with trim) at about 50 with 2 people on Stingray 198 LX. Does this seem a little over propped /?

 

[Scott Danforth]

propped just perfect.

 

[porscheguy]

Go see my thread titled 1990 Wellcraft eclipse performance data, for info on what you can expect from a reasonably wide range of props on a 19’ w/ 190 4.3 and 1.84/1 gears. You’re just about at the limit.

 

[alldodge]

Mercruser 190 hp tks 1 81 gear turning 14 x 3/4 at (4800 with trim) at about 50 with 2 people on Stingray 198 LX. Does this seem a little over propped /?

Some of these numbers are incorrect because I'm seeing a (negative) -42% slip, which cannot happen

14 pitch prop
1.81 drive
4800 rpm
50 mph

Is the tach accurate?
Are you using gps for speed (the boat speed-o is no good)?

If it was at 10% slip then you would see about 32mph

 

[porscheguy]

I think OP merely misstated his into and put down the prop diameter instead of the pitch. Whatever the case may be, everything he’s got should come out to 50mph or so.