Once the S2000 starts to generate heat around the suspension, it started to having this clunking knocking sound at low speed like driving around a parking lot. It wouldn't do this at high speed (or at least I couldn't hear it) and it didn't seem to affect performance but it was really annoying me. I resolved to fix this. First, the rear lower control arm spherical bushing had to go. It had started to wear and had a mm or so of play in it causing that knocking sound. This bushing doesn't really need to be a spherical so I opted to have it replaced with Hardrace hard rubber bushings instead. This is still going to provide good feel while improving NVH.
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| Hardrace hard rubber rear lower control arm bushings |
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| worn out sphericals |
The second fix was to allow the springs to rotate more freely as the suspension compressed and unloaded. This is achived by adding Swift thrust sheets between the spring and the perches so that it can glide freely and not bind.
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| Swift thrust sheets |
Finally, I wanted to fix the relatively low caster we were measuring on the car ever since I went with sphericals. S2000s should easily achieve over 5 degrees of caster and I was maxing out at around 3.4. The front control arms were removed and the spherical adjusted over to make the control arm sit at the appropriate angle and now over 5 degrees of caster is easily achievable.
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| Control arm spherical adjusted |
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| New alignment looking great |
Car drives amazing again with no more clunking sounds in the rear at low speed.
Maintenance Update:
Mileage: 67,150
- New Hardrace hard rubber rear lower control arm bushing (part no 7423)
- Swift thrust sheets on rear coilovers
- Reposition front control arm spherical bushings
- New alignment
