Originally Posted by
snuvet75
Thanks Martin. You mention in your app that low RC front with high RC rear will give more steering due to forward leaning attitude of the car. If that's the case, what you mentioned above(lowering front RC and/or raise rear RC to remove snap oversteer) doesn't seem to be going to resolve it.
Then you also say that high front RC with spool creates pushing into corner and snap oversteer out of corner.
So does high RC increase or decrease lateral grip? I'm so confused...
By its nature, setup is a confusing thing, because you can't look at changes you make in isolation, and you also need to think about what part of the corner you are in as well as are you on throttle, off throttle, neutral throttle etc.
Let me try to clarify some things....try
In that roll center section of the app there is a lot more information that needs to be taken into context, but I guess I should look at how I can improve that section to make it easier to understand. Having said that here are some key summary points that I think will help clarify things for you.
1) a lower front roll center will give you more steering on initial off-power turn in, but will push in the middle and on-power exit of the corner
2) a higher front roll center will push on initial off-power turn-in but give you more steering in the middle and on-power exit of the corner.
The reason why you can't just take the approach of assuming a higher roll center means more grip in all situations, is that you need to consider the longitudinal weight transfer (front to back to front) as you enter a corner off power and exit a corner on power.
For example,...
....the lower front roll center allows more weight transfer to the front of the car while turning in off power. This initially can offset the loss of lateral grip in the front due to a low roll center.
This changes through the corner however.
In the middle of the corner when the car is at neutral power not as much weight is being transferred to the front of the car and now the lower front roll center having less lateral grip than the high rear roll center will be more dominant, causing the car to push more in the middle.
On power corner exit, transfer even more weight on the rear tires causing it to push even more than in the middle of the corner.