The 1988 305 IROC-Z's had anywhere from 170hp to 220hp that could be had with either a 700r4 automatic tranny or a 5 speed tranny.
1986 305 TPI 190 HP / 285 Lb.Ft
170
170hp at 4400rpm
200hp and 260 torque
305 horsepower
305
130
The 3.7 liter V6 engine is rated at ( 305 horsepower )
very little
305 horsepower.
About 170
305 hp