454 Tune Up and Still Not Right?

[savatreatabvr]

Ok, I've posted a thread about this issue before and have gotten great responses, I've tried everything everyone suggested and it's still sluggish! I've put new plugs in it, new plug wires, new cap, new rotor and new vacuum lines! I set the timing, I rebuilt and adjusted the Edelbrock 1407 and adjusted the valves but when I take off it still sounds and acts like it's running on 7 cylinders! I don't believe I have a vacuum leak, burnt valve or flat cam lobe, it doesn't knock or smoke and the 3" exhaust flows fine! I've heard other vehicles through out the years sound like mine so I know I'm not crazy but I'm at my wits end hoping someone has had this same issue and know what my problem is?

[conman24]

Triple check your plug wires, and the timing.

[KQQL IT]

Flat cam time?

[f.monroe]

I had a 454 that I had to pull the timing forward on all the time. It would retard itself no matter how hard I tried to anchor my distributor. Old junky parts maybe. It sounded like what you are describing. I would just pull the distributor to advance the timing. If it had a little detonation I would back it down a little. I called it a seat of the pants adjustment. If I tried setting it with a light it would run like crap. Balancer was probably bad or wrong timing tab. I would just try advancing it a little to see if it helps. If so go a little more.
Frank