Electrical Surge with RPM

[His Dudeness]

Hey guys, I'm puzzled.

I noticed a while back that when I would rev the engine from idle, the headlights would brighten and you could hear the blower motor increase speed. Also, when accelerating from a stop you could see and hear the same things occurring. I chalked it up to defective voltage regulator and the alternator needed replacement. Over the weekend I replaced the alternator and the battery. Well, it still does the same thing and now I'm scratching my head.

What else could possibly explain this, or is it common and I should just move on with my life? Yes, I do lose sleep over things like this.

 

[Kernal]

@His Dudeness

What is the charge (volts) of the new battery after sitting a few hours (engine off)?
What is the charge of the battery (volts) with the engine at idle and at a steady 2000rpms
What is the idle rpm?
Are the alternator belts (both) tightened correctly?
Do you have any non-stock accessories that draw a lot of current?
What brand/size/type of battery, what is it's date code?
Did you check the charge of the battery before or after stuffing it into the vehicle?

Some thoughts: poor connections battery-alternator (corroded/damaged battery cables, loose/corroded connections, bad grounds), loose alternator belts, idle speed too low, defective new alternator, defective/discharged new battery, ----

If you can't measure the voltage (easy with a cheap multimeter), drive back to the autoparts store and ask them
to put their alternator/battery tester on the battery and run the diagnostic program.

Others with electron experience may have more specific suggestions (@jonheld )

 

[efjayatee]

Bad grounding

 

[His Dudeness]

@His Dudeness

What is the charge (volts) of the new battery after sitting a few hours (engine off)?
What is the charge of the battery (volts) with the engine at idle and at a steady 2000rpms
What is the idle rpm?
Are the alternator belts (both) tightened correctly?
Do you have any non-stock accessories that draw a lot of current?
What brand/size/type of battery, what is it's date code?
Did you check the charge of the battery before or after stuffing it into the vehicle?

Some thoughts: poor connections battery-alternator (corroded/damaged battery cables, loose/corroded connections, bad grounds), loose alternator belts, idle speed too low, defective new alternator, defective/discharged new battery, ----

If you can't measure the voltage (easy with a cheap multimeter), drive back to the autoparts store and ask them
to put their alternator/battery tester on the battery and run the diagnostic program.

Others with electron experience may have more specific suggestions (@jonheld )

The rig is down for the week while doing a regear, when back up and running, I'll run voltage tests.
Idle RPM is around 700.
New belts tightened properly.
I have a small under-seat sub/amp, but it doesn't create much of a draw
Batt is an Interstate 24F 750CCA. I don't have the date in front of me, but I buy direct from the dealer truck, so I know it's a good fresh batt.
I did not check charge state prior to install.

All batt and alt connections are clean and secure with no corrosion. My suspicion is poor grounding, or idle speed is too low. What should idle speed be on these?

 

[jonheld]

What should idle speed be on these?

650 rpm at normal operating temp.