Setting the timing on my 4.9 I cannot read any numbers on the tab, I can only see the marks. I know that 10 btdc is the big notch, but which way is toward 0? Is it toward the top or bottom. Like I said stupid question, but I can't read it nor find a suitable image.

 

I don't have a 4.9, but it's easy to figure out.
10 BTDC is 10 degrees before top dead center, so if the crank turns 10 degrees further it will then be at top dead center, or 0.

 

Let me clarify a bit now that I'm home ans relaxed a bit. I'm more used to the 302, which has a fixed pointer and the degrees are marked on the harmonic balancer. On the 4.9 the timing tab is marked for degrees and there is a fixed mark on the balancer.

I know where on the timing tab to set the mark on the balancer for factory timing specs. What I'm unclear on is whether moving the mark counter-clockwise (when standing at the front of the motor facing it) will advance or retard the timing. The only reason I ask is I'm trying to advance the timing as is recommended here, and want to be sure I'm doing it right.

 

Assuming a 4.9 turns clockwise when viewed from the front (like every other Ford I've had), then moving the timing mark counter-clockwise will advance it.

 

Simple enough, thanks

 

Also, your idle will usually increase when advancing, decrease when retarding.

 

This info from Steve83 might help: 1983 Ford Bronco General Purpose Pics picture | SuperMotors.net

 

That made it all make sense. Thanks