1/4 mile times with a bb in a 72 duster

I have a 71 dart that is a full body street car with a 360 magnum in it with a small camshaft like a 498 with a 727 and 3500 stall with 391 rear and dot Hoosier and I ran 12.30-12.40 figured this car would be quite a bit faster is nothing but. A drag car striped our inner fenders gone all aluminum pannels in back idk I guess time will tel was told it weighed 2700 with the old set up