In that case, no. Adding weight to one side of the bucket holds more potential for more harm than good.
By the way, why are R4 rims stopping you from adding ballast? I personally didn't want to fool with bolt-on weight, went with liquid ballast instead. Installed price was $237 to add 968 pounds of RimGuard (803 rear/165 front).
//greg//
With respect to the harm, are you thinking of damage to the FEL or something else? As to ballast and R4 tires, I have water and antifreeze in the rear tires. I think the total weight is something like 335 pounds per tire.