Originally Posted by jcp123
... and an MSD billet dizzy, but no box.
That said, since it was modified, would the lack of the EGR have any effect on it still? I would presume that it was tuned to run as it was set up from the rebuild.
The MSD distributor is the wild card here. It probably had a 'non-EGR' curve so that would rule out the distributor as the source of the knocking.