Shower should have nothing to do with your issue. Your prop (from what I'm reading) is ventilating so its getting air between prop and water, If the prop is to high above the bottom of the hull it will ventilate. Just wondering how long has this done this (new to you boat)

It should be a 23 Mirage Plus. If its not a Plus then it doesn't have the extra cupping

Success!
 

The boat does have a 23 Mirage Plus. Took off the drive shower and it ran perfect!!! Wow! Thanks to everyone for responding.

Next question- when running the steering is great, when idling the steering is very stiff. Is this the norm? Just replaced the helm, but did not replace steering cable. This is a 2007 Outlaw 26 feet. Thoughts greatly appreciated.

Where was the pickup for the shower, in the front of the plate or very rear?

Nice job Speedy........

drive
 

It was located in the back below the cavitation plate, and it was a double, two pick ups.

got her done
 

Thanks!! LOL!!! Got to get these issues fixed, summer is coming!

I was actually talking about F-2 Speedy, the guy who diagnosed your issue. Glad it was a simple fix.

Don't see how pickups, or for that mater much of anything else, behind the prop have anything to do with air getting in a prop. If it was in front or above the prop (like in a surface drive) then sure, but in any case glad your running good

It can introduce air, which causes cavitation, like the aeration tubes on 6's but on a smaller scale.. Well known and well discussed, especially on single pickup showers when the pickup is put on the wrong side.