Depends on what year it is. Chevy had some 350s in the 70s rated at 155hp. Pontiac had 400s chime in at 225.
Smog motors were prettly low on the HP ratings, some are just in the design fo the induction system and Cam. You may have a 230hp Factory moor that makes 300lb-ft of Torque. Won't rev very high, but will pull very nicely.
2006 Mustang GT in Torch Red
C&L Intake, Evolution Performance Tune, Borla Axle Backs, Hurst Shifter, 4.10's, JBA Long Tubes, Prothane Engine Mounts, Steeda UDPs, FRPP Charge Motion Delete Plates
84 Bronco, 302 C6 on 32 10.50's