Well, I finally had a chance to run the SP-1 on our regular track. Unfortunately it's not behaving as well as before. Namely, I seem to have a lot of on-power understeer. The changes I made were
* 185mm setup with the option parts
* Carbon-reinforced plastic upper and lower arms
Otherwise the setup hasn't changed. I tried to run the links inward (so, out on the pod, in on the chassis) with harder side springs, but that didn't seem to help. My theory is that the stiffer front arms actually reduced my steering, as the softer plastic would give a lot more. I'm only saucing the front tires 50%, so I could sauce 75% or more. But that could easily result in nasty traction rolls.
So, what should I try first? Softer front springs? Stiffer side springs or thicker damper oil? Does diff tightness play a role here? I hesitate to make too many changes at once, but I definitely need to do something to get more on-power steering.