I have a 2003 SeaArk 1872JT with the factory jet tunnel. I have the leading edge of the jet foot pretty much lined up with the top of the tunnel and it runs awesome in smooth water and riffles, but when I hit any sort of standing waves (even small ~1 foot waves) it cavitates really badly. I keep reading about transom and tunnel extensions helping with the cavitation issue. What is the best way to attach a tunnel extension to the boat? I've heard people mention UHMW and aluminum. I do not have the ability to weld aluminum myself.
If anyone has photos of an extension that works well, I'd love to see them.