I'm no engine expert but I have built, raced and dyno tested a bunch of BB Mopars for all kinds of applications, race, street and strip and street only. I would look at using one of the Comp Cams grinds, Magnum 270 H, 280 H or maybe one of the Xtreme energy grinds like the XE262H or the bigger XE268 H grinds. I have never seen a stock unblueprinted BB Mopar be anywhere close to blueprint specs . from the factory on any part of the motors My message is that Imperial motor problly doesn't have a true 9.0 to 1 compression ratio now with the new heads, you can do some measuring on the deck hieghts to see what it ends up with as far as the current parts, if it is above 8.5 to 1 comp ratio then think about what you want to do, if it is below 8.4 to 1 I would probally try getting it closer to 10.0 to 1 with the new aluminum heads and use a bigger cam than the ones I recommended, maybe the Comp XE275HL or XE285HL grinds IHTHs