[Dick Boneske]

Stock jetting on a manual trans '65 is .063" in the center carb, .068" in end carbs. Anything above .065" for the center carbs would be rich to the point of black smoke from the exhaust--- and unless you're running a very radical cam grind, unnecessary.

Royal used .070" or .073" jets in the end carbs. I usually use .070" jets to replace the .068" jets. If there's an aftermarket cam, sometimes .073". I remember a guy at Union Grove Drag Strip back in the day with a GTO with a radical solid roller cam who removed the end carb jets completely to richen the WOT mixture. Exhaust looked like a Diesel through the quarter mile, but he ran very well. His name was Ralph Tatum.

Originally Posted by aceaceca

I am also currently pondering jetting for my 65 tri power. I have confirmed Royal Bobcats got .070 in outbound carbs. I have not found reference for center carb but I believe it was .068. If my memory serves me I feel we used to run .070 outbound and .068 center. I might start with the old set up. What goes around comes around.