I'm the self appointed worlds expert on pinging:
What car do have?
Is it stock, if not what mods?
If the car pings with all settings (eg timming, etc) to specs is one of the foll
owing:
carbon build up causing increased CR. CURE= pull head and decoke. Since people
pay big $$ to increase CR you can increase the octane gas you use, or use an
additive. Try cooler running plugs, richen the mixture a tad, or RETARD the i
ignition.
Vac leak causing the mixture to be lean (worse when under load) causing the
comb chamber to run hotter then pre-ignition. CURE= fix vac leak (look at
conections into the manifold, carb-manifold, and manifold to head). Use
carb cleaner to locate leak. You might try a richer mixture to counter the
extra air, but this is a fix of the symptom rather than the problem.
Runing too lean caused by carb out of adjustment, or air filter not in place.
CURE= adjust carb, put in air filter.
Ignition too far retarded. This could be caused by dizzy slip (not too likely)
worn dizzy, perhapps bad points or wrong points gap (incorrect dwell). CURE=
check and set timming, (I always set mine static, but a set back timming gun
will allow you to set the timmimg and see how much advance the dizzy gives you
at certain revs so you can compare to specs), check and adjust dwell by
looking at points gap. See how much play or lateral movement the dizzy shaft
has, it should not have ANY, even a little side play could result in erratic
timming.
HOT spot in the comb chamber, caused by one of the above. CURE= will vary
depending on the reason for the hot spot. If you remove the head, remove all
corners in the chamber with a Dremel tool to prevent hot spots, but do not remov
e much as this could decrease the CR. BTW increased CR caused by carbon build-
up might have to be removed as these tend to glow red hot and make the hot spots
In answer to your question retarding the ignition timming will decrease the
chance of ping. If you are retarding it back past the specs something else
is wrong.
Cheers DW Exit
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