the lurching under acceleration was a fuel problem, most likely an excessively dirty fuel filter.
the explosions are no doubt related to replacement of the distributor, possibly you have the plug wires crossed somewhere. explosions in the exhaust are caused by unburned fuel in the tail pipes or mufflers, resulting from a cylinder that isn't firing (or in this case, not firing at the right time).
your friend on the DTBB, George
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