How does cam timing affect DCR?

[blykins]

Hey, anyone that can use their brain will suffice. Unfortunately, mine's not working right now....because I used the .050" durations when I was supposed to have been using advertised durations on the DCR calculator.

One question first though. When I look at a timing chain sprocket, the "retard" numbers are towards the clockwise side of the sprocket. Say 0 is at 12 o'clock.....4 degrees retarded is at like 2 o'clock or 3 o'clock. This is where I'm really confused.

By looking at the timing gear this way, and not moving the cam shaft at all, you would have to move the crankshaft CCW 4 degrees....right? Or am I totally looking at this the wrong way? And if that happens, then yes I can see where it would look like advancement of the cam instead of retardation.

I must be looking at something totally wrong here.....or I have too much time on my hands to think theory.

Anyway:

The cam IVC is at 50 degrees ABDC at .050". Seat to seat, it's 69 degrees ABDC.

My SCR is right at 10.95 I think. DCR with the cam straight up is 8.45.

With the cam 4 degrees retarded, DCR is 8.16.

I do think I want to run it 4 degrees retarded...just to help out a little on piston/valve clearance and top end power.....but now I'm thining that the combustion pressures may not support a DCR of 8.16 and a SCR of 10.95. So I may have to get a little thinner head gasket...

I do plan to take my time and check piston-valve clearances, etc. However I just wanted to know where I stand before I start.