Miata Mailing List: October 1992, Message #31
sponsored by



     


   From: (none)
Subject: Re:  Another Gasoline/Pinging Question
   Date: (none)

Jim:

In addition to the things discussed previously, timing has a large
effect on pinging.  If it's too far advanced, you'll experience lots
of pinging.  If you have a timing light, it's relatively simple to
check this yourself (tho I've not done it yet on the Miata).

Assuming the timing is o.k., you might want to see if an intermediate
octane rating would help.  There are usually 3 grades where I fill up:
87, 89 and 92.  When I notice pinging (it's usually on hills around
Pittsburgh) I switch to 89 octane for a couple tanks.  THat's always
worked.  Using a higher octane rated gas then you need just dumps
lead into the catalytic converter.

An interstate trip where you can keep rpm's about 4000 for several
hours might be the best thing, especially if you do mostly city
driving.

Elmer Beachley etb@cs.pitt.edu