For longer mains or to play it safe you can use a rear Xray diff with their metal gears. That is probably your only real option.
As for the new shocks. I was only able to run 1 test and I think since the pistons have larger holes I need to go even stiffer than I did. The ones I built where not what I was looking for and I went back to what I normally run. Since I was racing 2 classes and helping pit, I just did not have the time to rebuild more shocks and keep testing. I think I will try them again with 70 wt oil next time. The track has a lot of direction changes and you need a car that changes direction very quick.
DJ Apolaro