curious of approx power output..

[rx-tang]

its a long shot to be guessing but i don't have enough experience with this motor to know what to expect...
it a mid 80's 302.. non roller lifters.. stock heads..
cam going in is a melling... adv dur. 280/280... @.050. 230/230 ....
performer manifold, holley 650 double pumper, holley blue pump, couple other bolt ons... would i be close if i was hoping for 280hp out of the motor?...