Maximum advance

[David Hunt]

It would seem from the discussion below that coming up with an appropriate
model is absolutely essential!  I can't get one hour on a dyno, much less
pay to train a couple of people to help me.

dh

> With a copper pipe bolted on the head and connected to a "stethoscope" on
the other end, across a fully soundproof wall, you will hear >even isolated,
spurious knock bursts and be able to back off timing very quickly. For this
process to work well you need to stabilize the >engine at every load/rpm
points and adjust them individually, and you need silence and concentration.

Why copper?

>soon thereafter you'll hear an erratic burst of noises somewhat similar to
what you hear when you lit a
> match, only much shorter, slightly standing out of the huge background
> noise.

I've read that the ping is actually ultrasonic and that what is heard is a
subharmonic of the signal.  Did you see that on the scope?

Can I guess that your method would be only for one barometric pressure and
one octane level.  If so, how do you compensate for changing atmosphere and
gas?  Is that the 2 degree bake off?

dh


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