Originally Posted by DeliveryValve

Personally I don't think going to 18-19mm in the rear sway bar will not be too drastic. Both R107 and w116 has about a 19mm rear sway bar and a 24mm front sway bar from the factory. The smaller r107 handles pretty good, but has a completely different front suspension setup - rear is the same as the w116, w123, and w126.
Since I bring up the w126 chassis, the offered swaybar setup is 24 mm up front and 13 mm out back with an optional 17 mm rear on some models.
Now the w116 has a similar front suspension setup and rear suspension as the w123 and w126, but I'll tell you, I'll take the factory w116 handling over the w126 any day. My experience, those factory w116 will out corner any factory w126.
In taking what Mercedes offered, I think an 18-19mm rear swaybar will help immensely on a w123. I don't even think oversteer would be an issue with this thicker bar.




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