OP
IF...... my 367 felt BB strong, even just 400BB strong, that would be 400/367=Plus 9%. Applying that logic, to a stout 318+.020, would make it feel like a 1.09x323= 351cubes. While you can make a 9.2Scr 318 feel stronger than it is, with stall and gear; direct gear and 3.55s, will always reveal the truth. And for a cruiser, stall and gear is the wrong way to go. That leaves just cubes, Effective pressure, and supercharging.
The cruiser useage, throws up a wall for the 318 at about 2400 and 3.23s. That leaves just pressure, supercharging, and overdrive. IMO.