9 seconds on 9 inches???
Caltracs are not a magic pill that makes cars fast. For what it's worth, after spending $1000 on the full Caltrac setup (links, mono's, shocks front and rear) and tuning it for a year, I still can't beat my best 60' time on BONE STOCK SPRINGS....no joke. It is more consistent on the Caltracs, but if your car is hooking (which mine was) then you probably won't gain much if any. Just my opinion and observation. One of my friends that races a Valiant put Caltracks on this year, his car runs exactly the same as it did before...again, his car was hooking fine prior to switching to Caltracs.
If you are running a T-brake I would get rid of the 8 3/4 while you can still sell it in one piece and get a dana. If you car is nice and light, and the 8 3/4 was back braced it might last...hard to say...much better to sell it while it is in one piece in my opinion to off set the cost of the dana.