magnum casting numbers and engine quest question

Fair enough,
Unfortunately in Australia we don't have as many options on parts as the usa and next to no magnum stuff at all. I even have to ship intake gaskets from the usa as I can't get them here. It makes it expensive. For example, if I was to ship the EQ heads it will cost me $100 per head plus tax of 10%. So once I get the $1139 plus $200 and convert it to the aussie dollar and ad our tax it's $2061 landed. Not saying the usa parts are expensive, it's just the added shipping that's a pain. But I chose to import a magnum engine so I have to ware it. I just don't see the point in spending my money on a 40 year old aussie la engine but that's just me.
I think you could be right with the hp increase as I remember reading a guy on this for used a cam a tint bit bigger than mine with eq heads and hit the 400hp mark. My cam is fairly small though at
216/224 @ .500

Personally I think the EQ's set up nicely for that is a heck of a deal for good heads.

Oh, there was so a good joke in there, and I'm passing on it. :D