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Ok now this is not for the average boater who leaves his engine on the normal transom settings.
This is for those who have their engines jacked up high for the mega speeds.

Why are the anti-cavitation plates still left on the motors ?
with an engine jacked right up it serves no purpose at all, and is just extra weight hanging around.
considering people are doing everything possible to save weight I have wondered why this has not been deleted from the motors.
There are lots of surface piercing outdrives that do not have the plates, and lots of foreign
ali baba type boats that don't have plates.
so why does everyone with an outboard keep them and even have them repaired if they get a crack or a bit of damage.
when running a full surface prop is this just a splash guard ?

when lowering a hydraulic plate to get the best holeshot and trimming right under this plate again gets in the way of water flow.

so what is the reason for keeping it on a very highly jacked up race boat ?

or do some take this off ?

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I've never seen one removed. I know some omc's have cooling passages in the cav plate for the l/u bearings...

You still need to get out of the water from the hole. Same reason why guys add drag plates to give you even more traction to get going to me would be the reason you wouldn't remove it.

X2
The weight savings is a none issue. It would be less then 1 lb.
The difference in hole shot is where it's at.
I can't say for sure, as I've never seen an OB with the plate removed but I'd think the hole shot would be brutal with out the hydrodynamic effect.
Adding a drag plate to my XR02 made a huge improvement to hole shot. I can only speculate that removing the existing plate would have a comparable negative impact.
Not to mention you'd likely fall off plane trying to go around a corner.
If someones got an old case they don't want donate, I got a band saw!

when race boats are running with their engines right up the plate is no more than a splash guard.
but I suppose on these holeshot don't matter .

OK when we talk about holeshot, what about drag racing boats with the prop out the back with
no plate ? these pull away rather rapidly .

I can understand those who have hydraulic as they can use both low in water and high etc.
But on a boat with a fixed engine that is running with prop high it seems a pointless thing.

might just be me ,cant see the wood for the trees..



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I'll test your theory.
Send me a 12" case, preferably an XR-6.
I'll test it with the cav plate record the results then cut it off and retest.
Letcha know how it works out.

Some of the yamato race outboards dont have any plate and they are like rockets for hole shot..

Clearly it does make a difference on your typical go fast lake boat. I have watched first hand significant hole shot performance on boats with no change other than adding a drag plate. I agree as well as there is not much metal in the stock anti cavitation plates to make much of a difference when you can skip dessert and acheive the same weight reduction before going out.

"When you can skip dessert and acheive the same weight reduction before going out."

yeah I know what you mean, but that's like telling people who get lightweight engine covers not
to bother with those too.

Yes and no - there can be sometimes a lot of weight to reduce there and we are coming full circle here in that a lot of boats would appear to lose performance by shedding this piece.