my buddys got a 5.0 makin around 375 on motor. it's pretty stout.... but theres a guy on the other side of town with a 91 that has a built 598 c.i. motor in it with the 5.0 emblems still on it and i think it makes bout 9?? on motor and 13?? on spray. i think i heard he was on passtime. like a week or 2 ago.