The 360 magnums had a .474 lift cam. I'm not sure what the 318 had. My buddy took a stock magnum 360, added an airgap and 750,HEI module conversion with a 4spd behind it,323 gears and it does 13.40 in the 1/4
I don't think .474 lift.... I thinks it's .410 for the magnums also. The 318 mag had more lift than the 360 mag, not by much, but a little. They had 245 hp (net) from the factory, which is 5 more than the '72 340, and more torque.
But yes, 13.40's is very reasonable with that combo. With just a 4bbl and headers, it should be over 300 gross hp, and about 350 ft lbs of torque.
