I increased the width of the center section of the BNV by 4 inches, only changed it's width not length. Being now that the center section is 12 inches wide making total width 50 inches what should the new cg be?
This shield give you a rough outline of where it needs to be. Once you have it around there then you should throw it like a free flight glider and move stuff around to see what works best. You won't really know for sure until you've experimented with it for a while.
I did basically the same thin only even wider.. Turns out the CG really didn't move much from the standard blunt nose. Start with it just a little further forward and see how that goes.. I will at least be fly able there. Mine flys great..