I can tell you this - it is a kit that is designed to work with a door actuator (electric automatic) to lift them. You can tell that by the holes on the throw arm. If the car they were on didn't have electric actuators then it's no wonder they sagged. Likely only the throw struts were installed and this didn't provide enough weight to hold the door up, so they likely began to sag way too quickly.
The way it would have worked is two struts would (should) have been used on the lower part (you can see the darkened areas of the holes that were probably caused by the struts working as the door opened). Then the other two holes on the arm above the dark holes that look clean would have had the door actuator hooked up to it. Seeing how clean they are I'm guessing the actuators were discarded. These type of kits are usually used with electric door poppers, and then the actuators lift the doors on their own. The method of installation by the prior owner was probably not a primary cause as to the hinges eventual sagging.
You can use them on your car, but you're either going to have to obtain, hook up, and wire in the correct door actuators that are supposed to go with the kit, or upgrade to higher psi strength struts. My opinion is that the excessive strength forced upon the hinge without the actuator has probably weakened the throw arms slightly, so the hinges are never going to work as they would have new. You can band-aid the problem as mentioned and they'll last, but they'll never be to the level they should have been because of shoddy (i.e., rushed) installation.
[This message has been edited by Fiero84Freak (edited 08-23-2011).]
