Dealing with spark-knock/pinging

[Guynn <amx69@xxxxxxxxxx>]

Greg,

Myth Busters just did the ''moth balls'' make more power in gasoline 
bit. They found their engine more powerful with the moth balls.

They did not however do any research as to octain increases.

This old ''wives tale'' has been around a very long time.

In my opinion the reason you are having the ping is because now the 
engine has a bigger plenum area to pull from. There is more available in 
each intake pulse and the cylinders are filling with more volumn than 
before. This more filling in turn causes more cylinder pressure, the 
increased cylinder pressure is just enough to require higher octane fuel.

You should TUNE an engine for the FUEL it is using. By that I mean, you 
CANNOT use published tuning specs for 1968 on 2005 fuels. The two fuels 
are worlds apart in their makeup.When AMC published the Tune Up specs, 
those specs were established AFTER much testing. If, big IF, AMC were 
still building cars today, then those engines would have different tune 
up specs than our older engines simply because the FUEL is different.

Go look at some currect design pistons. This new fuel is running so much 
hotter in temp than old fuel that manufacturers are moving piston rings 
down the bore . They are having to move the top ring to get better ring 
life as the heat is killing the rings. Get a 390 Badger piston built 3-4 
years ago, and get one that is currewntly built. Compare them side by 
side and you can easily see what has been changed. This is just one 
piston example, there are plenty more.

Regards,

Randy Guynn