When you heat metal it loses some of rigidity, if you cool it fast (use water, cold winter weather, etc.) it will get very hard but somewhat fragile. I guess that this is why nev's springs snapped, they got hardened by too quick cooling.
You can get rigidity back by hammering hot metal, but it changes a bit of other properties.
I had some metalwork lessons in school over 10 years ago, just basics, however I don't know proper english terms
They'll also deliver such coil spring as you like. Prices were kinda cheap if I remember correctly. Vallilantakomo also makes sway bars etc... Pajakulma is mainly a heavy duty supplier but they'll also make springs for passenger cars I guess.
Volvo R-Sport - Equipment for the car enthusiast.
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