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F83 is significantly heavier than F80/82 (~120lbs front ~415lbs rear) and BMW's OE springs for it are stiffer as a result to maintain the same ride height. For example, for the comp pack, the front F83 spring is 7% stiffer than the F80/82 and the rear is 32% stiffer.
The EMD front spring rate (194lbs/in) is just slightly less than F80/82 comp pack front and the rear (645lbs/in) is identical to the F80/82 comp pack (but linear and not progressive). In fact the rear EMD spring rate is 15% softer than the F83 base rear spring.
It wouldn't surprise me if your bottoming out feeling is coming from hitting the bump stops and getting deeper into them a lot sooner than you would normally. As for rubbing under compression, check the liner near the outside edge of the wheel well at the 10 o'clock spot. It protrudes closer to the tire there and with your spacers you'll be getting even closer to that.
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