White Water at CFRC

After last weekend, we had some good information on what settings were good and what needed attention. The worst part was that we were still fighting the steering; I am unbelievably over it. I decide to swap back to stock knuckles to see if they have been the problem all along. Once removed, Shaun lets me know that at some point I had bent the driver's side knuckle! Eureka! We have found why the car has had so much steering problems! John re-aligns the car, giving it a near OEM setup so we can figure out the steering for sure, make sure no setting is akward and causing trouble.

We set out for CFRC and the weather calls for rain. Being optimistic, we arrive and change the rear tires as the course was soaked (and it was still drizzling). By the time we got the tires swapped, rain seemed to play along and left for the night. With it already dark out, there isn't much chance the course will dry, but at least it won't get worse.

We added grip to the setup since last weekends ajustments, and even in the rain, the first run tells us we went a little too aggressive with it. There is so much grip that when I was on throttle sideways, the car wanted to straighten up. It is really nuts to see the ASD knowledge play out in your hands. I sure hope I am able to really get a handle on it, but I think I'm headed in the right direction!

A few adjustments are made to loosen up the car some and we head back out. Car breaks away pretty well, and I have a decent feel for the car under throttle and off. It is behaving a good bit considering the river rapids we are navigating.

I hang out some big angle; I'm really impressed what stock knuckles can do with just a drift standard rack spacer. Then it happens.... STEERING BIND. Its still here! It wasn't the knuckles! All night I kept making really similar runs but it kept binding in the same areas of the course causing either an understeer moment or a spin. Not only was it binding, but it was worse than before. I was only able to link the course when I played it safe on angle, which won't go over well with the judges in competitions coming up.

While packing up, I start talking with a few other drivers, comparing my setup to theirs. Nothing really is different. I have a new rack, a new LCA/ball joint, new tie rods, stock knuckles, standard alignment.... nothing stands out as an issue. The only difference I can think of is my large spacers in front. I put spacers on partially to fit the wheel to the fender, but also to move the steering arc away from the tension rod so there is no contact at high angle. On the trip home, at 3am with nothing but white lane markers flashing to keep me company, I start thinking hard about what could be going on. ASD classroom flashback, and eveything falls into place. The change I made, when I made it, what the issue is, and things that compound it.... it ALL aligns to the same thing. Those spacers and my scrub radius.

To get technical, scrub radius is a relationship of the supsension geometry in relation to the tire contact patch. I have effectively made the steering more resistant to my inputs, and more prone to interference from bumps/suspension travel. The solution is fortunately simple, get smaller spacers and correct this large positive scrub radius. Some alignment settings can help this issue, but those settings would hurt the cars performance in other places. We shall see soon! Our next scheduled event is Road Atlanta in just a few weeks!