I had a decent outing with my Diggity DC4 / Associated TC4 based car over the weekend, taking second in 17.5 touring despite a mountain of tuning changes and fighting (eventually beating) traction roll through sweepers. On the upside, I think I found a way to keep the car from tweaking and ruining it's handling.
As a caveat, I was running on Jaco Blues and for some reason every car I have run on blues runs like it has a broken shock or something, complete garbage without making big tuning changes not needed in other tires. BUT they were the local spec tire so I had little choice. The car felt like it needed more rear toe-in, but I had left my toe-in hub carriers at home so I was stuck with stock toe.
It ran semi-impressive laps, and I should have been happy with it but I can't help but feel that with the amount of time and work I put into the cars chassis and suspension it should have been faster or easier to drive. I have a few more tweaks to try, and maybe it was just old jaco tires, but I guess I will see in the future. This dog can definitely hunt, it's just not as aggressive as I wanted it to be.