Question for the metallurgists

[Ghoste]

The leaf springs in my 67 were rearched by a previous owner.  I'm just wondering how long that typically lasts before they settle out again?  Does it alter the characteristics of a leaf spring when you do this?

[Chryco Psycho]

it should last a long time unless the structure of the metal is damaged , steel has awesome elasticity & will not lose the memory of the original shape
the best way to make a car handle is to use a Flat leaf spring , any added arc allows more leverage to deflect the spring sideways while cornering 

[Ghoste]

So if the leaf sits level now, then either it has settled OR it was never actually rearched and I'm just noticing it now?  I think it sat higher in the rear before though in this case.  For one thing, the snubber has started banging the floor like mad of late.  The rearching would likely have been done about ten years ago.
In any case, it doesn't matter.  In about 6 hours I will be the proud new owenr of a pair of Hemi leafs from Eaton Detroit spring company. (how long have I been threatening to do that Neil?)