Vegas/OMC Prop Advice
I am in the process of reworking my 1988 hull
schedule to be finished July 4th. I am completely re-rigging from
skiing the kids to going fast. I have added a 10” set back and
Bob's nose cone and hydraulic steering now......what prop?
The point is I am a 120 female reworking this boat. It looks great
and I wanna go fast. I have the racing experience. I have been
given many choices of props...which one is the right one.
I am running a 20 foot Vegas hull with an OMC 200. It is my
understanding that I should be able to run at least 82mph. My
reworking the hull has made it approximately 150 pounds lighter.
Also, confirm my math of motor setting = 1/2 inch height for every 1 inch
Sounds like you have a nice project boat being formed. Here is my honest
opinion. The Vegas with the OMC should run around 5" of set back. At
10" the 450 lb motor will cause the boat some bad handling
characteristics compared to 5" or even right on the transom. I've set
up the Vegas with a 225 Yamaha right on the transom, 1 1/2" up and
had it run in the low 80's. There is no reason yours shouldn't do the
same. The cone is good. I'm not entirely sold on the hydraulic steering
for 80 plus boats. I've rigged and driven them and the owners and myself
find the boat a little more difficult to control than with mechanical
steering. It ok, but you'll find the corrections to keep it on the pad are
different than the norm. The 1/2" for 1" set back formula is not
a given. It depends on the total set up and the boat angle of attack. I
don't know where the figure came from but disregard it. For now set your
boat up with the 10" jack with the propshaft centerline 1 1/2"
below at neutral trim. This is a good place to start. It might be a little
low but only go up till the wheel torque starts and the roostertail is
getting higher than the motor. If that happens go back down a little and
you’ll be set. For props a 27 or 29 OMC SRX would be good. Any Mazco RE3
or big blade chopper around 28 pitch would also be a good choice. Make
sure of a foot throttle and that all steering play is taken out and you
should have a good ride. If the boat is flighty and kind of unruly to
drive at top end take half the set back off. The boat is more predictable
with the weight closer to the center of gravity.
Good luck with your project.
whatever questions you have to IHRTechTalk@yahoo.com.
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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.