I have a p-dub brass front bulkhead, tyre weights stuck on top the servo and 3 in each triangle next to it. I also have the battery fully forward and one layer of tyre weights under foam filling the rest of the battery tray back to the gearbox. Red front springs and silver rear springs.
I just wish I could get my 4x4 to handle anywhere as near as good as the 2wd.
