318 cam
With NO modifications (assuming a 318 2bbl.)- not upgrading the springs, not eliminating the valve rotators (if present), or anything else, then just slap a stock 360 2bbl. cam in there: 278/278 .410/.410. It's not much, but the rest of the valvetrain isn't going to handle much more than the stock 318's 240/248 .373/.400 cam.