Back in my youth (early days of the internal combustion hot rod) I would take the car out & run it up to 7g or so, if it didn't hit on all 8 all the way there, I would go back to the garage & drop in the next size bigger jets. Repeated the process until it sounded right. Lookin' back that could have been a receipt for burned pistons but it worked at the time.

I'd go the other way when the plugs looked black.