Holley/Demon Carb stumble

I was doing some research on line and so guy named Lars
had a article on basic set up on a Speed Demon Carb

He said that the Demon had 3 lines on the sight glass and that for street you should set it to the lower line............
Does that mean the upper line is is for Race?????????
He didn't say that but I *** um ING
And got me thinking about a higher fuel level.
Wanted to send the link for the article, but can't find it now.