What's the best oils for tappet cam engines?

Im going to run Northland 20/50 racing oil in my 273 S motor, cheep at 4.00 a quart and contains one of the highest levels of zinc on the market today.

my supplier tells me it has a higher level than most additives can supply per can. besides its a real pretty blue in color when fresh.

Been running it our sportmod motors with wix filters and never had a motor failure yet due to oil or lubrication problems.

Very pleased. ;Lon