[rdorman]

Reading air/fuel on plugs with today cleaner burning fuels is very difficult. It can not be done effectively with the naked eye and it may take some time to even get them colored and then that will be over the whole RPM range so you still don't know! Gone are the days of warm her up, put in a new plug, blast down the quarter and read it.

The only way you will know for sure is chassis dyno, or a portable analyser. You can still tune a carb with out these but it always seems to take a month of sundays.

Multi spark discharge units generally do not like the platinum plugs. Go get the cheapy autolites and save some bucks!

Rick