I'm in the process of installing a new Garmin 8612 Chart Plotter. My Fountain 38EC has a cored hull which unfortunately eliminates several of the recommended Garmin in-hull transducers. For anyone using a similar Garmin Chart Plotter with a cored-hull boat, I'm curious which Garmin transducer model you are using? Thanks.

You just need to use an appropriate size hole saw and remove the core. After getting the cut started, don't forget to remove the drill.

Padraig

Try it first before cutting/drilling. Epoxy it solid the the lowest portion of the hull.
It will likely work just fine.

My boat's transducer works perfectly when I'm going slow, but it has never read very consistently while I'm on plane. From what I've been told, with some step-hull boats there really isn't a solution for elimination under hull bubbles (cavitation). The main reason the steps was designed into the hull to reduce water surface tension, and infortunately transducers don't like air bubbles.

I'm on the fence as to whether it's worth adding a more modern transducer because regardless of type (in-hull or thru-hull) it will still be dealing with the same cavitation conditions. Unless I can find a better solution it seems this is something I may just have to deal with.

SR-71

As long as you can get to that spot, mount in forward of the forward-most step. Active Thunder mounts there ahead of their (single) step, and it works pretty well except at top speeds when the hull is leaving the water.
IMHO, I like the transponder there. When inching into a beach or whatever, that can tell you when it's getting TOO shallow before your drives/props get to the shallow spot.