Big Problems with New 408 +PICS

• Cylinder 7 Intake lifter will not pump up and making noise.
  
• Carbon/Oil deposits on valves of Cylinder 7
  
• Thick ridge on Cylinder 7 compared to others
  
• Smoke coming from left tail pipe at midrange RPM. Or when after high RPM and let off gas, we were unable to tell which or if the white smoke had blue in it

So, the lifter is bad and needs rebuild/cleaning or replace but why? And is that related to the ridge on the same cylinder? I'm worried it may be a valve or Edelbrock machining problem...

Specs: 408 Eddy heads, 650 Mighty Demon, Racer Brown .470/232 and lifters, HV oil pump, CC Pro Mag rocker arms. 4 speed. At most 200 miles on engine and 2 runs.

Ideas?