302 swirl port heads on a 360
302s work very well in 340/360 applications. The right ones. If hp is your goal, then it's not the right setup. They will make mad torque, and will be very strong up until about 5500. That's where my 360 gives up. Mine I ported to the larger intake size, but really didnt make the rest huge. It's enought o smoke the tires in 1st and 2nd in my Swinger, and pulls fine in OD with 3.55s at 1500rpm.
For your use, I'd suggest a set of factory Magnums. They have better ports, and the chambers are even smaller than 302s, in addition to having the larger valves. Basically bolt on too.