So I bought this long block Marine application 454 for 400.00 new on the crate . Now I'm going to put a roller cam in it and maybe another set of heads . So I looked at the Comp site and they have a few that look decent but not sure on what to expect on the bottom end with a big block . So K5 spec's are as follows : 78' , 10/12 bolts with 4:56 gears Locked front and rear 36" tires TH350 with mild stall . Now the engine will have stock marine application bottom end and probably a set or Merlin cast iron heads and dual plain intake and headers going through 2.5" duals all the way out . So I want lots of bottom end but also want it to spin up good and not fall on it's face at 4000 rpms . So is going with a retro fit roller with around 218' intake and 224' exhaust at .050" going to be good or a little big ? Will I notice a drop in bottom end performance . Should I go with the next step down which is like 212 & 218 ? it will also have a set of goood roller rockers on the top end too . All info and experience appreciated .