all things being equal on a 440 which cam would make more power old 509 or lunati 240/250 520/547 cam.....

Now if you want to turn up the wick a little,
running 440ez/Eddy/MP Stage 5's or "other"
bolt on aluminum heads, with a bigger carb/intake
and headers, I would look at the Lunati or bigger
juice sticks from Hughes or Comp Cams. If you are
a horsepower junkie who runs the streets, a good
small solid or roller with good lift will do well
too. Food for

Ran them both in RB 440's and in a 451 low deck, that Lunati will walk the dog on the old 509....take it to the bank. In the 1/8th mile I ran a 6.96 @ ~96 mph in a 3200 lb 73 duster w 3.91 gear on McCreary dirt track tires with a 3500 stall fairbanks, Self ported 452 Iron heads 10.7:1 shortblock with 6.36" rods, M1 and a tweaked 830 Nascar carb....The lunati was about equal to a 509 up to 3500 but much stronger above 4500, worked best in my motor at 104ICL (hit the vert harder and I had to go up in tire size to get her to hook. I ran the pro-parts headers and the flowmaster pulse techs phased 180, (which picked it up over a tenth in the 1/8th once I jetted up) that was one nasty sounding motor, really unique sound for the pre 'X-pipe" days.

509 is no slouch but that lunati was one of those grinds that they really got right for the old wedge. I sold that cam to a guy in California that put it in his 440 tunnel ram "pleasure" boat

I wound up de-tuning the duster to the old single pattern 230/230 .515 Hughes (engle) once they shut the local track down, that was a really snappy daily driver.