1987 Ford 460 won't start after new distributor has spark have done the 180 degree turn nothing but some backfires?

If this is a new symptom that was not with the old distributor, check the armature on the distributor shaft. This is the part under the rotor that rotates past the stator. It is held in place by a roll pin. If the roll pin is not in place, although it maybe snug, the armature can spin on the distributor shaft. If that is not the problem check for the same condition with the drive gear on the bottom of the shaft. It is held in place with a roll pin as well. Do not assume because it is new, it was assembled properly.

If the engine was doing the same thing with the old distributor and you are sure you have the firing order correct. Check for slack in the timing chain.

In case you don't know this can be done by turning the engine over one way by hand and then the other way while watching the rotor. The slack in the chain is the number of degrees on the crankshaft pulley you have to move before the rotor starts turning the other way. If the timing chain has more than five degrees of slack it should be changed. It would probably require more slack than that to cause the condition you have. Keep in mind the chain might of jumped a tooth on the gears.

If that is not it check the camshaft gear that drives the distributor for damage.Good luck