I have pulled out my 400sb and am almost done with the 454 install. I have been using the Holley 2D system with no problems but I am unsure if it can support the larger engine. I do have a line on a new (buyer changed his mind) 4Di system for $500. They are normally around $1300. Has anybody run the older system on a big block with good luck? Should I just put on the bigger one? Thanks.