On all of my cars in the past, including Sarah, I typically run larger than normal street tires. (275 or 295 series radials out back) On the street, I would always run 10-12psi in both air bags to keep the wheel mouldings from cutting the sidewalls. At the track, I run 7psi in the drivers side and 27psi in the passengers side. This combo has worked well on all of my cars and my current one. Best 60ft I ever had with my old '86 T-Type was a lazy 1.45, with those pressures and these old school parts: Metco rear sway bar, SSM rear lower control arms, stock rear upper control arms, 90/10 shocks in the front, Sears specials in the rear and no front sway bar. Car weighed 3670 with me.
Air bags are a cheap tool to help control launch manners on all G-bodies.
Patrick