this sounds like a really hi tec project.the stuff you would need would be found in a testing lab.outside of finding a spring scale that handles 100's if not 1000's of pounds and attaching the rope and pulling with a car and watching the results i can't think of any sort of home made gizmo.i would not want to be the guy watching the spring scale when the line busted!!!


i used this old spring scale when i was deer hunting years ago.
it go's up to 500 pounds,more or less.