My 2011 VLX and 2022 LSV  

Appreciate all the responses.   5 of 5 boat shops at lake Tahoe (6'200 altitude) have all said it's the prop.   Running the 15+ pitch doesn't make sense.   They point to an Acme 3311 (18x14).  I'm going to give it a shot.  

Update:

The timing is now set at 703@1200 rpm and the fuel pressure is showing a steady 58 psi!!!!  It's almost as exciting as the cow having twins - lol!!

Shout out to all who took the time out of their day to respond and help a guy out!  The nearest dealer would not even work on this boat!  Told me that he was not interested is working on anything that was 10 years old and especially if it did not have the original engine.  All I was trying to get him to do was re-flash the ECM to the original zz383 tune! Geez.  The second closest dealer said they would have to talk to AL and then get back to me but never called back.  I'll try it on the water and then decide if I think it's worth re-flashing.  Maybe with iron heads the 5.7 tune will be okay.

Thanks to @csleaver for further explanation of the HVS:  It turned out to be off a tooth.  Your instructions were invaluable.  This is what this forum's purpose is!! 

The second new fuel pressure regulator (which was a automotive 4 bar) seems to be steady at 58 psi.

The roughness is gone, the over rich loading up is gone, the exhaust is no longer visible, and it will idle after the closed loop.  I guess I am not qualified to say whether it was the regulator or the timing that was the most significant change but it seems to run 100% better at the moment.

I was taught to not count the chickens before they are hatched so I will drag it back to the lake and try it on the water.  Then I can work on the other problems i've found! Ha!

I'm tipping my hat to you guys right now...........

Thanks

Headunit power and ground (or whatever the input is that you're using, like maybe a bluetooth dongle) should be comping from the same place too.

Try to determine if it's the input or output side of the EQ.  With power off, unplug input RCAs then power everything up and turn on the boat.  If the whine is still there, then it's the EQ or downstream of the EQ.  If it goes away, your problem is upstream of the EQ.

If upstream, try a different set of RCAs, and potentially a different source.

If EQ or downstream, start with moving the internal ground jumper in the EQ, and then move to switching out RCAs and eventually amps.