I'm bringing this back to provide an update on the installation and provide initial feedback on performance for the first trip out. I did a ton of research before buying the 165T-50/200-SS260 and did not find very much information so it seems appropriate to post some up now.
The mounting location on a Parker 2530 (or 2320 or 2520) is ideal because the bottom of the deep V has a flat area that is perfect for the 260 sized high speed fairing. This puts the transducer face at the deepest point in the water. Also, I have twins on a bracket so there is very minimal to no issues with cavitation in turns and the props are 5 feet behind the transducer.
My big error for the day was leaving my USB memory stick at home so I did not take any screen shots. I tried to take pics with the phone but it was too bumpy and did not get a single clear shot. But next time out I'll take several and post them up. It may be a couple weeks.
The first sea trial was in non-ideal conditions with 5-7 kts of wind and a short interval lump from the night before. Location was Santa Monica Bay in SoCal. I ran out about 9 miles in the lump to the South Bank and the DFF3D and 50/200 sounders were in Auto Fishing mode. Both provided clean signals at up to 18-20 kts and a couple times I got some air with a good 2/3 of the hull out of the water and did not see any noise. Normally I'd not run the boat like this but I was testing the transducer performance.
Once out at the South Bank in depths of 165 to 230 feet I started playing around with the sounder settings in Manual mode. I ended up with the following settings:
DFF3D Multi-Sounder - Manual - Gain 50 - Clutter 35 - Auto Range - Short1
B164 - Manual - LF Gain 60 - Clutter 25 - Auto Range
B164 - Manual - HG Gain 60 - Clutter 20 - Auto Range
I had the TZT2 on split screen with the Multi-Sounder on the left and the 50/200 on the right in dual LF/HF mode. Running at all speeds up to about 20 kts the signals were good and clean.
I then ran over to Torrance Beach from the Short Bank which crosses Redondo Canyon to test some deeper water performance. Running at about 18 kts the Multi-Sounder seemed to start dropping the bottom at about 400 feet. I'm sure this is just a need to tweak the settings but I was on the move to get to Torrance Beach and was bouncing around too much to mess with it. The 50/200 (B164 in the combo) tracked the bottom fine to 940 feet LF.
And I did do a little fishing and kept one vermillion rockfish. It was delicious!