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Old 10-31-2017, 07:21 AM
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SSLance SSLance is offline
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As much as I like my new big Stoptech brakes (and trust me, I LIKE them a lot...) I think I'm more happy about the steering geometry changes... I'll try to describe to you how it changed after adding the new ATS spindles and reversed steering arms, but I'm not sure I can do it justice.

I see autocross cars on course all the time with a ton of static camber dialed in to help the outside front tire grip in corners, but at the same time...you look at the inside front tire in a turn and maybe 1/4 or sometimes even less of that tire's contact patch is on the ground. The owners or drivers will say "Well, the inside front tire isn't doing anything anyway, so what does it matter?"

If the inside front tire grip in a turn doesn't matter, how can doing something as simple as adding Ackerman make such a dramatic change in the way my car turns?

Every car that is setup to turn should already be optimized to get 100% of the possible grip from the outside front tire...that is a given. After that, the only way to get even more front grip is to help the inside front tire. After this latest change to my car, I can tell you that when you do, you WILL feel it!! I first noticed the difference when I went to my testing track (large cloverleaf interchange with 25 mph long sweeping corners). Mid corner, steady speed about 85 mph, I could put just a little bit of steering wheel into it and the front would turn and almost simultaneously the back would step out just a tad and the whole car stayed perfectly stable. You could feel the inside front just digging in every little bit of wheel you put into it. My eyes opened right up...it was that much different.

The only real change to the steering geometry after adding the spindles was the addition of a bunch of Ackerman. I'm not sure how much I added, heck...I set the toe alignment with a tape measure and didn't touch anything else on the control arms after the install. I know this though, I almost didn't have enough tie rod length in the adjusters after flipping the steering arms around. The ride height ended up exactly the same, travel the same, maybe a bit more camber gain at full compression, everything basically the same except the added Ackerman. We accomplished this by putting the driver side steering arm on the passenger side and visa versa, this made the steering arm curve to the outside instead of the center of the car increasing the amount the inside front tire turns in relation to the outside front tire.

I autocrossed the car with the local SCCA Region for the first time last Sunday. We had a super fast course with two LARGE and fast braking zones. One had a sharp 180 degree turn at the end, the next had a hard 90 degree turn right...then the whole back stretch was a long wide spread out slalom...all perfect to test a car out on. The only knob I adjusted on all day was brake bias, way too much rear brake early, then not enough so I kept putting it back in a little at a time.

What I found though is I could carry WAY more speed into just about any corner, and when I turned the wheel, it just turned and stuck. I got to where at the end of the second straight I'd brake early...then let off the brake and just carry max speed into the hard right. It stuck EVERY time and the Ackerman helped turn in tremendously. In just 4 runs, I never did find the limit in front grip...there is so much more there...it will take the driver more time to get used to all the new found grip.

Results showed I finished 6 tenths off of Keith Lamming and 5 tenths off of Patrick Darling on a 45-46 second course. Not too bad at all considering they are accomplished drivers on 335s and 315s and I'm on my puny little 275s and in a heavy car with 57% of the weight on the nose. Just goes to show, a properly setup car can be fast...even without being perfectly balanced front to rear. Setting your car up to get as much grip from the inside front tire as possible is just another tool to have in your bag of tricks.
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1985 Monte Carlo SS Street Car
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