[bobcowan]

There's no magic in a spark plug. Expensive platinum and iridium plags have a coating on the elevtrodes so they last longer. That's it. Just to last longer. That's how they to advetise 100K miles between tune ups.

I use standard Autolites in everything. Simple, economical, never had a failure. In my stret vehicles - truck, wifes car, Harley - I change them about every 40K miles. The cobra goes through 2-3 sets a year. At $1.50 each, I don't worry about changing them.