What the minimum and maximum voltage u could run...say a 100.4...or 4500d...what would be the safest for a 16volt system for a 4500d?

u wont get an exact answer on the 4500 because they are only tested at what the specs state.

Just like my aq3500d is only rated up to 18v, people have ran them up to 20v flat for quick instances but not suggested for daily use.

I would imagine the 4500d "should" be able to handle a true 18v setup regulated at 19.2v but dont hold me to that.

Most 12v amps go up to 15.5 -16v. You can get a more precise answer on the smaller amp.

15v max for the 100.4

4500 d =no higher than 18.5

I coould have swore jacob told me the 4500 could take 19.2...so I guess I need to set my alternators at 18.5 then..then voltage drop will take it down a little more

I coould have swore jacob told me the 4500 could take 19.2...so I guess I need to set my alternators at 18.5 then..then voltage drop will take it down a little more

yep 18.5 for the 4500, 15 for the 100.4

I coould have swore jacob told me the 4500 could take 19.2...so I guess I need to set my alternators at 18.5 then..then voltage drop will take it down a little more

No, they will not -- 18.5 is where the circuit is set and tolerance can vary 0.3 volts either way.

1500s, 2000s, 2500s, and 3500s will handle a higher voltage.