This is why I waited so long to upgrade the brakes on Barney, because I knew a spindle change was the only way to do that part right...but the spindle change was going to change the front end geometry that Ron and I spent so much time refining years ago.
The spindle pin height of the new ATS spindles was very close to the same as the original metric spindles they replaced after swapping the lower ball joint shorter pin in so I left all of the alignment adjustments as they were when installing new spindles. Handling both on the street and the track was awesome right away, these spindles gain camber faster and the result was even more turn in grip than before. They also push the wheel out 0.25" increasing track width by a half inch, also good for handling...but with the increased camber gain plus the track width, the outside edge of the front tire tread began to have significant contact with the inner fender in compression. The steering arm is also different which is great for additional Ackerman, but at full compression the tie rods were contacting the frame.
This is where putting race car geometry on a street car gets complicated...packaging. I am the only one that I am aware of that is putting this kind of tech onto a stock chassis G Body so sometimes it is trial and error until we get everything to play nice together.
Ron Sutton and I decided we'd try a stiffer front spring to keep the front from traveling so much, 600s to 700s. While I was making this change, I also raised the front ride height about a half inch higher than we had run it successfully before. More on this in a bit...
Thanks to coil overs these were both pretty simple changes to make in my storage unit garage. I did however have to run it to an alignment shop after to clean up after the adjustments. The shop was busy and I was short on time so we got the camber and caster set right where it was before then set the toe. The toe change was significant enough due to the ride height increase that it took the camber and caster settings out of our preferred range...but we didn't have time to redo it all once again.
Two days later I raced the car with Arizona SCCA Region on a fast wide open course with several fast slalom sections included. As I hit the first slalom section, I knew something was wrong right away. The car wouldn't turn in at all, just slid the front tires. This is something I haven't had happen since Stage 1 back in 2013. After braking for a normal autocross turn, the front was awesome...the whole balance was awesome. A bit tighter than before but very neutral. Basically the contact patch was great with the front compressed but when weight wasn't on the nose in a slalom not so much.
I made some shock adjustments and driving adjustments and got thru the day okay. The front is still traveling enough at extremes for the tire to just kiss the inner fender, not really an issue but close enough that if we lowered the car anymore, it would become an issue again. Our choice now to further refine the setup seems to be to either adjust the camber and caster at the current ride height back into our spec window or to lower the front some again, add bumps stops to keep tire off fender and tune alignment settings. I'll have to wait for Ron to finish moving his shop and get caught up again before making that decision. I'm good either way as I know where we want to be...I'm just not sure on the best path to get there.
This is where it's great to have a man like Sutton to help when venturing where no man has gone before...
Here is a pic of the current ride height...not quite 4x4 territory high but not slammed either.
This is where it was before
It is between 1/2 and 3/4s of an inch higher...wild how that little of a change can affect so much.
Here's a video of a couple of my runs from Saturday. Not too exciting but maybe a bit of a reward for those that read this far down...
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1985 Monte Carlo SS Street Car
Brian Hobaugh SCCA National Tour June 2014
First Hemi 'Cuda Convertible Ever Built
Short clips: Goodguys Pleasanton autocross and pit videos
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