I have gone threw some changes on my Gbody (bracket not stock) at one point ran this:
Front: Stock SBC spring with 1 coil removed, loose front suspension with poly bushings,lower arms "level" with ground,5 inches travel, cheap 3 way shocks set driverside 70/30 pass.side 90/10
Rear: Eibach lowering springs,boxed lowers with poly, adjustible uppers with TRZ joints in the 12 bolt,single adjustible shocks, single air bag (7 to15#), -2 pinion angle. 30x9 radial slick
Car would leave hard 1.44 to 1.46 but twisted bad and was a handfull down track.
After many upgrades, double adjustible shocks all around, HR&stuff bar,no air bag.
The car leaves straight and now can be driven down track with one hand.
Since someone mentioned the bracing ,which these car NEED, here you go.
I am new to the "stock" deal so I don't know how much of this is "legal"
I made this up for another board.

GM body braces, forgot to make a legend on this one:

Now the tuff one to do, overlay:

Hope you enjoy."