How to build a 13 second 340 Duster

Back in 1970, I bought a new 340, 4-speed Duster (b-5/b-5, bench seat, manual steering/4-piston disk brakes, 3.55 suregrip). With just a re-curve on the dual point dist. and a little playing with the jets on the stock avs carb. I ran 13.80's and 13.90's with the factory E-70 polyglass tires.
A year later, when I put a 440 in the car, I was told, by my machinist, that my 340 was a six-pack motor with single 4 barrel intake on it.

Seems like it wouldn't take much more to get it to where you want it to run.