Something seems way off. I am no engine expert by a long shot, but having 10 that won’t pump up doesn’t seem right. There is usually a distinct noise that goes along with a bad lifter, at least on most motors. Let’s hope the engine Gurus chime in and give some insite.

Hello ViperTony, I posted this for you as well on the Alley.

I think you may need to provide more information.
For example: what type of rocker arms are you utilizing? Are they T&D, Harland Sharp or Jessel? When they were installed were the oiling holes pointed up? Where is adjusting screw set in relation to the locking nut? How much spring pressure- static/mid lift? How was the valve lash set after Zero Lash?

I find it hard to believe that 10 lifters collapsed all together; On slow bleed lifters they will bleed down rather quickly during any type of cranking tests, especially with tighter valve springs and they may not pump fully up until you’ve run the car for several minutes- Cranking the engine does not count! I would suggest to run the engine for at least 5 – 10 minutes prior to checking the lifters and condemning them.

Additionally, if you were running as rich as you suspected;

– You cannot get an accurate reading of the Fuel Trims if the plugs / 02 sensors have to subjected to over-rich conditions which results in fouling.

– Any tuning that doesn’t respond adequately should not be performed with Catalysts’ in place. I strongly recommend removing the cats and thoroughly inspecting them on BOTH the in/out sides and check for expansion / contraction.

Best of Luck!
Doug Levin