BFG Comp T/A drag radial? They haven't made the Comp T/As for a few years other then the Drag radial. On the street, I'd run 30 psi, at the track, 13-15ish.
Well stock tire pressure with 245's for that car would be 30psi.
With a wider tire, you now much go lower, so try around 25psi. You really need to experiment and see. Every tire/car will be different, but the wider the tire the lower the pressure you can run due to increased surface area touching the ground