@3rd Gen Guy That should put you close to a CTS-V in performance. 0-60 should be around 5.4 seconds. Not a bad rocket ship, considering you built it for autocross.
@3rd Gen Guy Are you going to upgrade the rear-end, what are you thinking? I have a 12 bolt planned for mine, but I know they are much heavier than the stock 10 bolt. (9 inch is too typical, I'm a contrarian)
I've been brainstorming for ultra lightweight axle for racing. maybe a lightweight 9in full floater cambered 8.8 AXLE setup or I'll go crazy and build a custom GM 8.625 axle with an aluminum housing and 9in bearings.