I have installed someH&R W124 (self-levelling) SLS and special equipment lowering springs to my non-SLS 300E AMG. One of my front springs snapped and I thought it best to change all of them, the rear AMGs are no longer made and H&R seem to have the best reputation.
Am I correct in assuming that the SLS rear springs are higher/harder then the non-SLS items? I only assume this as I have read here that Merc Sportline Wagon SLS rear springs are used on non-SLS saloons. I have an ICE install in the trunk so I thought it best to use the hightest rear-lowerring springs available!
One last question. Which way up should the springs go, flat part top or bottom?! Thank you

No... springs used with SLS are lower/weaker than non-SLS springs. That's because the SLS "shock" is actually a hydraulic spring leg that supports some of the vehicle weight, unlike non-SLS systems where the standard shock doesn't support any weight at all. Later W124 AMG models came from the factory with the same Sportline springs as regular Sportline models, not AMG-specific springs with HWA- part numbers. While the H&R stuff will probably work fine, the factory Sportline springs would also work, assuming you select the correct ones for your car (using the "points" guide in the EPC).

http://www.w124performance.com/docs/mb/W124/124_suspension.txt

With a bunch of ICE in the trunk, you may want the #28 rear Sportline springs, depending how high you want the ride height. On my car the #28s' with a 1-pt pad gave a rear height around 14.5" (from fender lip to center of wheel) with a full tank of fuel and empty trunk. An extra 40-50kg of ICE may lower than 0.25-0.50 inches further. (??)

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Dave
Boise, ID
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