XRAY - Model racing cars

I was at a local track last weekend practicing for Las Vegas. I was runnig the stock rubber tire class and by the main, it seemed like there was so much traction, it was slowing the car down. After the race, the time sheet showed that everyone fastest laps slow down about 3 tenths. I know that the traction at Las Vegas will be even Higher, should I put on stiffer springs to reduce the traction as the race goes on to keep the speed up? This will be my first big race so I don't know how to approach the traction issue. Also the car had no hint of traction rolling which I was told was going to be a problem. My setup is posted, Suggestions?

Since your running a one-way, I would assume that the car is most likely scrubbing speed because the rear is too tight. But it could still be a combination of the front and rear though.

The first thing I would recommend is to make sure your rear diff is running very smooth and that it is as loose as possible. Here is a post where I explain how to set the rear diff:

http://www.teamxray.com/xforum/viewtopi ... 3909#23909

From what I see in your setup, I would then try the following:

1. Raise front downstop to 1
2. Use light blue springs in the rear
3. Change to low rear diff height position
4. Close one hole on all four shocks
5. Change to violet/blue fr/rr spring combination and move their upper mount positions in one hole to #3/#4. This should somewhat maintain the initial spring stiffness of the softer springs, but they will progressively stiffen quicker and not allow the chassis to roll as much.