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      06-18-2021, 05:52 AM   #51
Second Lieutenant
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Drives: 11 128i 6MT Sport
Join Date: Sep 2010
Location: Rock Hill, SC

iTrader: (1)

Yeah, 65mm perch. In the swift part number:
- Z65 is the spring diameter in mm
- 178 is the length in mm
- 070 is the rate in kgf/mm

Swift springs are advertised as having less coils for the same height and rate as other springs. So compared to a spring with more coils, the swift spring will have more usable stroke before coil bind. Theoretically, if you replaced the ohlins springs with swifts and kept the rate and length the same the swifts would ride better. When you increase the spring rate it will get harder.

I chose the swift springs because I wanted the most usable stroke from the spring.
11 128i Space Gray slicktop
13 WK2 Deep Cherry
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