A 4160? Vacuum secondary? Secondary metering block or metering plate?
It's not making any power with that MPH.
The carb and ignition would be the first place I would look. Getting more than 850cfm from a small 1 11/16" blade carb take a bunch of work. Call me a doubter. Might have way too much jet in it.
Low compression and the cam being installed in a bad ICL won't help.
