IML - Vacuum and pinging

[dardal@xxxxxxxxxxxxxxx]

In addition to DB's comments, I would like to add the following.  Some pinging 
at this very light load conditions is unlikely to damage the engine.  I know, 
it gets annoying, but the temperatures are too low to really overheat and 
weaken the pistons.  One of the consequences of retarding the timing is that 
you retard for all 8 cylinders.  However, most likely one or two cylinders are 
responsible for the pinging due to increased compression ratio by the 
deposits.  So, if you like your engine to operate at its absolute best 
potential, this retarding would be more of a temporary fix. You could try 
cleaning those deposits...
D^2
PS, some racing engines have custom distributors where they can adjust the 
timing of each individual cylinder to compensate for manufacturing tolerances, 
so all cylinders run at their optimum.  That would be too expensive for us 
though, and the difference too small, but worthwhile if racing.

Quoting Dick Benjamin <DickB@xxxxxxxxx>:

 Adjust the timing
> by
> ear to that point, and you will be very close to optimum for this cars
> condition.
> 
> Dick Benjamin