XRAY - Model racing cars

Hello all,
In the last race, I suffered from the following problem:
severe oversteer as soon as I lifted the throttle, especially at the end of the straight.

And I read in the setup book that this problem occurs when the rear differential is loose. I used 60K rear and 80K front (stock setup).
I tried higher rear and made things worst, because it did not solve the current problem but it created a new one, oversteer at corner exit on power, as expected.
Finally the solution was to go lower. 30K rear diff seems to solve the problem and provide enough steering on power too.
However, this is against the theory that I read in the setup books.
I would appreciate an explanation.
Thanks in advance
Dimitris

Well Dimitris in my experience i have noticed a lot of drivers overlook the basics and go straight chassis setup and tweak correction. The first and most important is tire traction. what tire shore do you use? are the tires fresh and when you rubb your finger across them do you feel a lot of resistance. How do you store your tires after a race. According to the condition you are having the vehicle is loosing rear traction and yes a lighter diff. oil will reduce rear wheel spin and therefore you will have some rear traction. Second does the track have high or low traction surface.

-Remove the shocks, disconnect the stabilizer links and make sure the suspension move freely with out any binding.
-Check the installation of the ball joint for the shocks and camber links as it is very important(user manual). I made that mistake and had the same problem that you experienced.

I will do that when I get a few moments to spare.