2003 Chevy Cavalier Timing Chain

We have replaced the timing components as well as the intake valves All the valves were bent after jumping time. After replacement we turned the engine by hand and the timing chain gets slack in it at each depression of the rocker arms. The slack goes away and the chain becomes tight once the rocker arms are released. This hapens for all 4 cylynders. This does not seem normal to us and can not figure out why the cahin would go slack. Note that the slack actually results in a kinck in the chain.