another stupid cis ?
 

77 2.7 cis Idles great with the vaccum advance unhooked, the idles like crap with it hooked up. Any Ideas?

this is a weird one.....

Check the timing with a strobe light. The advance may be closer to correct without the advance hooked up because the base timing is wrong

I timed it with the vaccum advanced pluged, and 3mm to the right of the z1 mark. Is this the correct timing?

If your car has the advance biscuit with the double hookups (one retard & one advance), then you need to have both disconnected and plugged prior to setting the time. The retard side retards the timing significantly at idle (10 deg or so?), but loses vacuum immediately when you open the throttle. So:

Get car warmed up, disconnect both hoses and plug them, set idle to 900 RPM, set timing to the correct spec (not sure what yours is, but someone here or your manual should be able to help). Double check after tightening dist clamp bolt. Then, connect both hoses again and reset idle to 900. Hope this helps,

ianc