If you have cars traction rolling, then i would suggest the following...

Btw, I am running 80 weight in the center shock, 70 weight works fine as well, just make sure you build the shock so it is very smooth.

Puprles and greys should be perfect for that track, if you are traction rolling or lifting even you can try supergluing the sidewalls of your front tires (traction roll is caused by the front, or so i am told, lol). Stiffer front springs or a softer back also works. If you dont have any losi hydradrive fluid then you can maybe use trinity red stuff, although i dont think it works as well. Maybe really thick 8th scale diff oil like 50k, but to be honest I am not 100% sure what would be the best replacement, since i have tried other things and they dont work as well.

and just a note, t-bar cars (incase you are trying to compare to find something that will work) need alot more dampening in the rear than a links car like a CRC or speedmerchant.