All 1991Pontiac Firebird models received restyled noses loosely fashioned after "Banshee" show car as Pontiac was developing the new fourth generation platform. 1991 Pontiac Firebird Trans Am's ground effects restyled as well. 1991 Pontiac Firebird base model available with 1991 Pontiac Firebird Trans Am ground effects. Trans Am and 1991 Firebird Formula receive new fiberglass constructed flat wrap-around wing spoilers. The new styling brought higher sales, up from 1990's sales. All L98 cars now receive N10 dual cats standard. Trans Am and '91 Firebird GTA get updated 2 piece taillights with "PONTIAC" scripted in orange across the panels. Center high mounted stop lamps move to inside top edge of hatch. '91Firebird convertible reintroduced. Firebirds with ttops were sent to ASC for conversion to convertibles. Previously ASC converted cars for customers but it had never been through GM. The '91 Firebird convertible was available with the LHO 3.1L V6, the L03 5.0 V8, and the LB9 5.0 V8. Production improvements led to use of new body sealants that added to the rigidity of the body.
