Steve,
The pinging is due to too much total timing. The springs and weights control
the rate that the advance comes in up to the total. You need to determine at
What total timing value the prevents the pinging (This is necessary to work
backwards and set the internal advance limit in your distributor) ... say 36
degrees crank timing, the initial should be around 16 degrees for decent
throttle response. This gives you 20 degrees of mechanical crank timing
advance (10 degrees in the distributor) The only way to get both top end
lack of pinging and bottom end throttle response is to limit the amount of
advance in the distributor by welding an advance stop in the distributor. A
factory distributor will typically give you too much total timing built into
the distributor and that is why they say set the initial at 6 degrees and
expect a total of 36 degrees. This gives you 30 degrees of crank advance (15
degrees in the distributor) so if you set the distributor for off idle
throttle response at 12-16 degrees initial you will have 42-46 total and
PING CITY. If you back it off until no more ping then you wind up under 8
degrees and you have a sluggish throttle response. Of course Camshaft,
compression and accelerator pump cams can all contribute to drive ability
issues that you need to tune around but timing is one of the standards that
is easy to set and forget. After riding in your car I would suggest 12-14
degrees initial and 34-36 degrees total with 22 degrees of mechanical crank
advance (11 degrees in the distributor) You would want to go with the light
to medium springs ( depends on which weights you use) so that all of the
timing is "in" by 3000-3500 RPM. You have been chasing this a while and if
you have the parts I would be happy to help out again. Perhaps you could
"fix" it once and for all.
One clear and simple fix would be to purchase the aftermarket MSD
distributor that is completely adjustable. I would even help you stick it
in. Besides you still need to go for a ride in my car with the new engine.
Best Regards,
Tim Ronak
Business Development Manager
Akzo Nobel Coatings
Off: (949) 305-5393
Fx: (949) 305-5394
Cell: (949) 289-3357
email: timothy.ronak@akzonobel.com
VM: (800) 234-6747 ext. 2257#
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