hey guys, need some recommendations for my new motor. i am currently running a fairly stockish 454 in my superstock mud racer and am looking for more cubes. problem is i need to pull 15" of vac at 800 rpm. so my question is what is the biggest cubic inch bbc i can build and still pass my vac test. i am a mechnic but not an engine builder, anyone have any experience with vacuum rules and bbc engines? i have all winter to build so any help would be appreciated.