i don't like beating a dead horse cause i know some may not agree with me but start looking at your ignition's primary wiring. your car is going on 25 years old. check all the connections replace wire where it is corroded or the fittings look corroded. the external resistors too. get all the juice you can to the distributor which will give you a stronger secondary spark.

with all that you've already replaced that ought to do it. i discovered this problem on my 72 350sl [450 eng]. that was all that was wrong.

another thought might be to check the charging system to be sure you're getting the 13.6 volts from the altenator.

good luck

__________________
Thanks Much!
Craig

1972 350sl Red/Blk 117k
1988 420sel charcoal/Blk 140k
1987 420sel gold/tan 128k
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