I believe they're accurate numbers but I'm still confirming ...
Spring rate isn't the only thing changed with the m030 kit though .
The differences in the height also effects car balance front/rear .... Porsche should have carried on using height-adjustable as stock .
And the arb differences also change the driving characteristics , and on top of that it as different alignment numbers ..
If I where you I'd stick with the softer springs and stiffer arbs
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