Wheel weights and loaded tires?

I have a cast iron starter weight (~70lbs) and two ~50lb wheel weights on each wheel. I am considering adding fluid to the tires to be used with the weights.

With a 26x12-12 holding 10 gallons for a 75% fill that would be 84lbs of water. So each tire would be at ~250lbs with water and wheel weights.

Any thoughts?