I have spent hours researching and looking at data and dyno sheets for the best engine combo for my needs. A 540 size motor will need to have a good( expensive) exhaust to see the full potential of all those cubes. Of course a full rollerized cam and valvetran is required that is matched to your exhaust. I chose to go with a 502 as I am using a 496 aluminm exhaust with a 114LSA cam. I want to be able to have a stable idle for good dock manners with no reversion problems with the stock exhaust. RPM dual plane intake outpowers the single plane until around 5,200 rpm for milder engines. Making 550HP with such a combo is not that hard to do so I would say get a good 4.25 crank kit for your 454 and let it rip! A 540 with nice headers, cam, single plane intake and dominator can make an easy 650-700 HP all day long but then you are now worried about your Bravo drive staying together? What are your goals? TBF