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      11-14-2011, 01:51 PM   #28
Pete_vB
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Drives: '69 GT3, GT4, 1M, 912
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Quote:
Originally Posted by MDORPHN View Post
Just picked up some very slightly used JRZ RS dampers from a fellow with a E92 M3!

Anyone have a good idea about how low a spring rate I can run with these?

Since the 1M is lighter than the M3 and my car is dual use (daily driver and track), I'm thinking about about something low -- like 350#/600#.

Will this work or would the JRZs be happier with something stiffer?

Neil
Score.

Did you get shock dynos with them? If not, any idea when they were last charged and rebuilt?

JRZs, probably including the RS, are race dampers with very low friction seals for low hysteresis. Due to this they will typically leak and need rebuild on a semi-regular basis- I've done mine a couple times. First thing I'd do is find a shock dyno and see what you're working with- if they need rebuild that can be done at the same time. From there you can calculate what spring rate range they are designed to deal with.

JRZs can be built up an various configurations and filled with various viscosity oils- knowing where they came from originally could also give you an idea of how they were set up.
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