Slant got me stumped

Hey guys, I have a 225 here giving me a fit and I can't for the life of me figure this gremlin out.

Started with a 73 225 single barrel..... won't idle below 1800rpm. Runs rough.iming showing like 30+Before. At first I thought it was timing because I couldn't get it to set and it would just bounce around. Inspected and replaced worn timing chain."slap the chain sides together"

Got timing not bouncing, but still acting the same. Rotated it to TDC and stuck the Dis back in....Won't run unless timing is high 25+....Rough

Same....Checked for wiped lobe and set the hot valve lash..That was fun at 1800+RPM...

Same...thought it was a bad cylinder or something..all checked out at 140psi +-5 and no bubbles in the coolant..so headgasket is good.....

Same..changed distributor,coil, and ECU with a known good

Same..verified fuel pump was pumping good.

Starting to look towards a vacuum leak/issue

Completely changed over to a Super Six 2bbl setup, verfied carb, and a remflex gasket..All ports plugged except vent

Same!......Gawr!

Autolite plugs look good..alittle on the black side..I caulk that up to it running like crap..They still have the washers on them.Head has tubes..But I think that would cause this......?

Only thing I haven't changed is the ballast...But I just can't see that being the root cause...could it?

Any other idea's?

Thanks