The new build will have a lower cg due to the choice of a 4S battery.
Old battery - 6S 4000mAH 40C, 695gm
New battery - 4S 5000mAH 35C, 573gm
However, the lower weight of the new battery could be a problem. I was running a 6S 5000mAH in the old build and the truck handled a touch better than with the 4000mAH. One option could be to bolt some solid steel bars to the inside of the TVPs just below the battery tray to get some more weight in the back. The rear of the TVPs will be completely solid this time with no cutouts and deeper due to the flat bottom so that might help.
The height of the new battery is about 9mm less than the old. The battery will also sit lower as the new battery plate will be positioned lower. So the top of the new battery should be sitting over 1cm lower than the old.
