BBC horsepower rating?????

[468chvy]

Was wondering how many ponies my 468 is putting out, I'm running mostly stock, have the 781 heads, an energizer cam, .510 lift, 272 dur., torker II intake, a 750 vac. sec., 3" dual out, anybody have an rough estimates, I know they have those dyno programs, but I don't want to spend the cash, and a dyno around here is over 100, so I thought I'd ask the forum, they're alot of knowledgeable people on here, lots of helpful info, so let me know your best estimate, thanks