dont heat the coil, I cant remember what the metallurgy is but its baaad.
Cut it with the thinnest cutting disc you can find to keep the heat to a minimum. I dont own a car that doesnt have cut springs haha.
If its a subtle drop I doubt you'd notice a great difference. If you are going much lower youll need stiffer dampers. Dont cut so much that the spring dislocates.
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