Offshoreonly.com - TRS nose cone worth doing?

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Hey guys. The purpose of a nosecone is to prevent prop blow out. If anybody has been thru it you know what Im talking about. It can be very scary. Prop blowout generally doesn't occur until around 85 mph. Prop blowout is when the regular lower unit builds up an air bubble around it approaching 85mph. When this bubble hits the prop the whole boat kinda falls down into the water as any lift you were getting is gone due to the prop loosing its grip in the water. Its like doing a nose dive at 85mph and the whole boat can totally spin out from the grip the bow gets when it falls. Very scary. The nosecone can actually scrub speed off your boat if you need lots of trim to run the boat correctly. Since it sticks out farther forward when you trim it it will create more drag into the water. I had one on an outboard checkmate with a 225 merc on it. It was actually slower than a stock unit. You mostly see it on boats that run over 85 with the height of the motor or outdrive allowing the prop to run even or higher than the bottom of the boat. It will also provide low water pickup for those applications. It is a general thought that unless your rig has natural bow lift and runs over 85mph spending money for it is a waste. I went thru it myself and found it to be correct twice before I learned.

I blew a drive 2yrs ago. I was not running nosecones, but wanted to. The replacement TRS I got had a nosecone. I thought this would be a great comparison between the 2. I can't tell the difference, trim angles are the same, RPM's the same, handling is the same and the list in the boat is the same. That dive does look cooler though. And the boat runs almost 80mph.
My $0.02

depeneds on the cone and speed . the hydramotive cone on my trs got 3 mph after 70

like i said. this guy is gonna be about 450 hp. so i may hit 70 if i can find a downhill part of the river...

Quote:

Originally Posted by h2oboater (Post 4254742)

I had them on my twin Trs Mirage race boat back in the 80,s did not see any speed. I have some on the Magnum I have now with raised Volvo driver same results. If there not put on properly there could be some determental results. If you look at many of the race boats running today in OPA how many have nosecones, not many if any. I there was some speed to be had they would all have them.
Raising up older drives like Merc Trs & even Volvo's to there optimum height & using today's props is were the speed is at. My Magnum I have now has old Volvo drives up 3" & Merc Mirage props, it works very well with or without the nose cones.

+1 same result

Also, it has been suggested to not put nosecones on unless you have hydraulic steering. A nosecone adds surface area in front of the pivot point of the drive. A lot of added stress.