S2 rear suspension geometry change
 

So... what actually IS the suspension geometry change from S1 to S2? What exactly did they change, and what was the effect? I get that there were parts changes, and that the intent was "better stability" or "better handling." What exactly does that mean? Different camber/toe curves? Higher/lower roll center? Less excess movement? I'd have thought someone would have figured this out and posted about it, but I can't find it anywhere.

The only hint I've found so far is this, from the PDF attached in this post:
Kind of suggests toe control was the point. But the wording makes it unclear whether that extra toe control comes just from the beefed-up upper lateral link or from the geometry revision as well.

Anyone have any input on this? Is there an authoritative source somewhere that I'm missing?

Found another quote here:
Source cited is Motor Magazine, but I can't find the issue online to verify.

Not sure if this is relevant but according to the guys at Racing Beat, their springs do not install from gen 1 to gen 2 with the same results in performance and ride-height.

Their gen 1 performance springs will fit in a gen 2 car but the rates are off and the ride height is off (rides lower in the back!), I have yet to find a good performance (street application) spring for the gen 2 cars that will improve the handling and lower the ride height (between 3/4" or more).

I bought a complete set of S2 rear arms for my S1. Other than the tie-rod arms being larger diameter (stronger) the lengths and the rest of the arms were identical to the S1 arms. And just so you know, the tie-rod arm is the lower lateral link, not the upper as was stated. So remember that as you read on ...


https://www.rx8club.com/rx-8-racing-...0/#post4686215


I thought about changing subframes, but considering I already changed the bushings to solid on my S1, the unknown factor of whether a used subframe would be true or not because about the only way to get one is from a wrecked chassis, and the all around hassle (you haven’t done anything challenging in your life until removing OE rear subframe bushings including metal sleeve/shell :uhh: ) decided it probably was BS if the arm lengths didn’t change.

The rear springs don’t directly interchange because they changed the spring perch position on the S2 shock. This is documented in the race forum area.


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If you replace the shocks with S1 shocks (stock or aftermarket), that problem goes away.

Yep, your OE shocks are likely shot any way