Setting the timing?

[skokie]

I was reading my how to rebuild Chevy small block book. I came across the part that says how to set the timing. It said that you need to point the oil pump shaft to #5,then back the timing back to 8 degrees BTDC & then line the rotor to #5. Now I am a little confused. Why would you do it this way? I have to be missing something.

Also the reason I checked into this was that when I removed the old balancer the keyway slot and the timing mark was at 0 but when I put in the new balancer the timing mark is 8-9 degrees past the timing mark which I believe is throwing off my timing a bit since when I have timing set at 12 for the HEI it runs like crap until I get the mark at what would be abut 14-16.

Any thought
Thanks in advance.