2.22L NA timing advance

[ejfluhr@austin.ibm.com (Fluhr)]

I recently bought a timing gun with an "advance" dial, and found out
that I was running with 3-4 degrees of advance on my 2.22L NA CIS-E
engine.  It pings pretty badly, though, with 87 & 89 octane in the
tank.  It seems to be OK with 93 octane.

3-4 degrees does not seem like a whole lot.  Is this really enough to
cause premature ignition?

On a similar note, how easy is it to change the o-ring seal in my
distributor?  It is leaking oil significantly.  Also, how do you all
clean oil off of the head, especially down by the spark plugs?

Thanks,
Eric
'85 Coupe GT, needs a good scrubbin'
---
Eric J. Fluhr                                Email:  ejfluhr@austin.ibm.com
630FP Logic/Circuit Design                   Phone:  (512) 838-7589
IBM Microelectronics Div.                    Austin, TX