The bigger the engine, the bigger the supercharger/turbo needs to be to make the same boost. In a boost application like this, a 420"+ engine wont make much more power than a 390"+ engine. Why does Goss ONLY have 404" when he could easily be using 440" engines? Its been said A LONG time ago in Gen III land that for NA build as big as you can afford, high boost builds seem to take ALOT more power with a crankshaft 3.80 or smaller and a rod 6.20 or longer because of block strength when you get over the 1000hp mark.