Vasseret YT/Optimax 150 Props

Randy,

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?

Thanx,

JP

 

JP,

Sounds 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.   

Randy

 

 

Please submit whatever questions you have to IHRTechTalk@yahoo.com.  All questions and answers selected will be displayed on this page as they come in.  Note: though all boaters are welcome, priority may be given to I.H.R. members.  Randy can not be held responsible for any advice given.  Though his information and expertise is second to none, he has no control over what you do with your boat.  It is up to you to boat safely and act responsibly, and his advice is only to be used as a guidance for your high performance boat/motor of which you are the one responsible for the risks involved.

Thanks,
Mark C.

 

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