In 1985, the 305 small block V8 was available with TPI (Tuned Port Injection) and finally in 1987 the L98 5.7L 350ci V8 engine became a regular option on the IROC-Z, paired with an automatic transmission only.
In 1985, the 305 small block V8 was available with TPI (Tuned Port Injection) making 215 horsepower and 275 pound feet of torque. In 1987 the L98 5.7L 350ci V8 engine became an option on the IROC-Z, paired with an automatic transmission only.