Originally Posted by
majicman
Brian,
First, Thank you for taking your time to post the good information that you have already regarding car setup. In reading though your posts you have given a lot of information regarding chassis setup, yet I find it a black art as I am not able to run at a permanent facility to validate changes.
I believe that some changes that are made are driver preference and track conditions. However, is there a mental approach or sequence of setup events that you focus on when working out the kinks of your car setup?
Some things that I have garnered from yours and other posts already:
1. Start with a known good setup for the surface you are running on.
2. Make one change at a time and test out. This is where my quandary comes in.
a. How do I tell that I have a car setup problem and not a driver setup problem?
b. If I do have a car setup problem how do I recognize what the problem(s) may be?
c. How far do you go with a single setup change (i.e Springs) before you are past the point of that change being effective and need to look at other setup option?
Thanks for any help you can provide,
Majic
Majic,
In order to recognize the problems, there are a few things I'd suggest. One is to have someone else watch your car carefully as you go around the track. It's good if this person is a fairly experienced driver. Sometimes he/she will be able to tell you things your car is doing that even you can't see/feel. Second, I think it is good to try to analyze your car's performance in a multi-part process. You have to look how it performs in both low and high speed corners. If you notice that you are slow in one or both of those, you must tackle it in 3 parts. You have to look at the entry, middle, and exit of the corner, and carefully observe what the car is doing in each stage. That'll help you determine what changes to make, because almost no change you can make will have the same effect in each part of the corner. Every setup change is a compromise. For instance, raising the front roll center will make the car initiate a little quicker, but it will roll less and feel smoother throughout the whole corner. This will make the car turn-in a little better, but as a result will give up a little steering in the middle and exit of the corner once the power is reapplied. If you make the same change to the front and rear, the balance of the car throughout the corner will remain the same as it was before any changes were made, it will just roll less and the car will stay very smooth.
You also want to think about what end of the car really needs to be adjusted. If you have an issue with the car loosing rear traction on the exit of the corner, then it's clear the rear needs to be changed, as the weight is transferred to the rear of the car at that point. If the same thing is happening on corner entry, but not exit, then it's a front end problem, as too much weight is transferred to the front or it is done too quickly. This is again a process of thinking about the stages of each corner.
Originally Posted by
IndyRC_Racer
Thanks for the info about roll center. I mainly run touring oval with foam tires and sometimes rubber tire on a tc3. Was having an issue with too much body roll when I switched to rubber tires . Didn't think to raise the inside of the camber links. I'll give that a try.
Going to see if we can get some people in Indy interested in this class.
IndyRC,
Raising the inside camber links will not reduce chassis roll. In fact, it increases overall roll, but it does it slower so that it does not build traction as instantaneously.