I'm trying to get a handle on exactly what rate my rear leaf spring pack is and while I've got things semi apart thought that it would be a good time to do this exercise.
My thoughts on doing it are to put a jack on top of a set of bathroom scales and wind it up so as to compress the leaf pack and measure the kgs ( to be converted to pounds ) required to compress the spring pack.
I talked to my mechanic about it yesterday and his thoughts were to maybe wind the jack up so as to compress the spring pack 1" then reset to zero and wind it a further 1" then take the reading.
Has anyone got some informed input on this? Do I need to compress just 1" or should I be going further?
He was also concerned about the car lifting up as I compress the spring pack but after having a trial run and compressing the springs a good 3-4 inches the car wasn't moving ( incidentally the scales were reading just under 90kgs )
Cheers
Dave

That sounds like the way to do it (1" compress). I'd also measure the car height to verify it isn't raising a mere 1/4 inch or so which would throw the scale off

Stock 1200 coupe leaf spring is rated at 109 lbs/inch

When you are asking leaf spring ratings are you inquiring on how much concrete you can load in your trunk or how much HP they can handle? I have stock leaf springs and am running a Ford Mustang rearend with probably 400hp. Maybe that might help.

Actually neither. As with the front coil springs I just want to know exactly what I have rather than guessing so I can then make informed decisions or when asking advice give accurate data when it comes to setting up the cars handling.
Dave

Good point, measuring is the way. They say that Leafs don't lose spring rate over time, although they do sag (resulting in less camber, which affects the load capacity). They can be cold-reset to alter or restore the camber

* rear Spring Rate is 109 lbs/in for a stock 1200 sedan or coupe
* stock leaf spring pack camber is 109mm +- 3mm
* rear Spring Load appears to be 468 lbs