Ok so I just found out today that the ESC is a different part number for a 305 TPI than a 350 TPI. When I pulled my 305 for my current 383 I never changed to the 350 ESC. Can this be having an effect on my performance? The car has never felt like it is making the power it should and tuning it has been difficult. I changed all the other sensors that were different such as the knock sensor and so forth.

This would be great if it would help me get closer to the power I believe I should be making.

I never knew there was a difference.
I've been using the stocker on my swapped 350 and I never had problems with spark.

My issues were always with fuel.

I didn't know there was a difference either. And I still don't understand how it would work differently. Anyone else able to shed a little light on this? Maybe Vader?

Would need a scan tool and look for any knock retard and spark retard to know for sure. No parts of your headers or exhaust touching the body causing any kind of knocking vibration is there?