Never heard that before. Most of the time the gimmick plugs are just that, a gimmick. Nothing wrong with AC Delco, Autolite or if ya really want to get something nice call NGK or Uridium for some of their plugs. The can help you chose which one is correct for your application.MNYPIT said:Hi, I have some AC Delco Rapid Fire spark plugs I bought about a year ago. Anyone know if I can use these with a Procharger setup? I know there are some spark plugs you should not use.
Several years ago I put some in my Astro van--I had it in the dealer service area and the technician said not to use them; some crap about them being for older vehicles where oil fouling was an issue. I asked him why they list the plug for all the new cars, but he didn't have an answer.AC Delco Rapid Fire
I run R5671A-9 or 10--I had to go back to a standard non-projected tip because I'm not about wasting the time to index the plugs to keep from closing the straps. I used to run projected nose on the motor, and non projected with the bottle. This combo hits the piston dome and closes the gap, so......... I try to find the coldest plug available--the 7AL-3 keeps em lit;never had a fouled plug no matter how it's driven. When running normal heat range stuff, the compression(14.5-1) would kill regular street plugs in short order--not fouled-dead!I run NGK R5671A-7