You've got to choose the cam to suit your compression, trans, stall, rear end ratio combination.
Just gonig for the most aggressive cam could make the thing lose power compared to stock in a lot of cases with holden engines unless the rest of the enigne around it is built to suit.
If you can give us an idea of your build then we can recommend from there.
I remember a mate years ago putting a 286 crane cam in a stock EFI 304 and ended up losing about 25rwkw compared to when it was stock because he didn't choose his cam to suit his engine combo as he had nowhere near enough compression.
Unfortunately with Holden V8's they aren't like LS engines where you have 100's of different cams available you can just slap in and send it.