Engine oil accumulators

So question. I’m wanting to run an accumulator on my engine, my question is how does this affect the oil capacity of the engine? For example, I know a “3 quart” oil accumulator actually only will contain 1.5-2.0 qts. So does this mean I need to add an additional 1.5-2 quarts to my engine, that way there’s the 7 quarts in the pan or am I over thinking this per normal?

Yes you need to add more oil to compensate for what is stored in the cylinder. With the cylinder full your dipstick should read normal. I use a cable operated manual shutoff valve on mine.