Vasseret YT/Optimax 150 Props
Here are some numbers that Iíve got from this summer.
The boat is a 1990, with a '99 150 Opti. Iíve got an older CMC hydraulic jack plate with both a trim gauge, and a plate gauge. With the 23 small hub Trophy, I get 60 mph on GPS, 62 on the speedo. RPM at 6000. Prop shaft about 3ins. below the pad and about 4 "clicks" on the trim gauge (quite a lot). Iím getting good lift, and it will start walking. With a 23 tempest, the numbers are pretty much the same, 62 on GPS. With a Merc 24 chopper Iím at 65 GPS, 67 on the speedo, at 6000rpm, about 2in. below the pad and two clicks of trim. Excellent lift, but she'll really walk here. I got a 28 Mazco with the boat, it came with a 200 new. This seems to be a little too much prop for the 150. 5600rpm, two in below and no faster.
I know the first thing that Iíll be doing this winter is pulling the engine and plate and make sure that it's set up right. Is there any thing else you can suggest (short of more power) that might get me a few more mph?
like the boat is running pretty good. The chopper number is the one
that I would go by. You may want to try a 26 Lightning ET.
This may run faster yet, and keep the rpm at 5800 - 5900. YT hulls
tend to chine walk a lot around 70. This is something that you will
have to master. But be patient, it just takes time. The 28
Mazco is too big for your 150. A 26 would work better, but I think
the ET would still be faster. I have had excellent results with a
Hydromotive 26 T4X 4 blade propeller. It does not work on
everything, but may work well on your boat. When this prop is
working good, it's handling is second to none. Keep the engine
height at around 2 inches, and try every propeller you can find.
This should get you started on going over 70.
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