1969 Dodge Dart Pro-Street 440

Got the bars all welded up as best i could. Painted them a aluminum color to keep the rust away. The reviews on these bars i think are on point, they are welded right and there is still some flex to them. I dont know if its sopposed to be like that or not? I figured they had to be super stiff, i have seen people jack up the car using the wheelie bars, and ive seen some that flex when the car launches too hard and they flex back.

Any one else make a set and can tell me the difference?