Re: Which Brand of Spark plug do you run??
 

AC Delco here too

Re: Which Brand of Spark plug do you run??
 

AC Delco forever. Kirk

Re: Which Brand of Spark plug do you run??
 

NGK FR5GP, just installed replaced AC FR2LS's.

Re: Which Brand of Spark plug do you run??
 

AC Delco 61-402 with a 0.035 inch gap.
Haven't seen any test results which show there is a better choice.

I plan to change them every few years.
This is in contrast to new cars with platinum plugs and their 100,000 miles change interval.

Re: Which Brand of Spark plug do you run??
 

What Plug are the NOS guys running? I'm thinking of going to the colder NGK TR6. Anybody use those, does the car suffer N/A when the NOS is off?

Re: Which Brand of Spark plug do you run??
 

Off the top of my head, NGK, one temp range colder, iridium tipped, gapped at 50, as instructed by Marc.

Re: Which Brand of Spark plug do you run??
 

AC/Delco (dbl platinum) and still look great after 10yrs.
I pull one every oil change to take a peak.

Re: Which Brand of Spark plug do you run??
 

Can't believe that no one is running the Accel Silver Tip, bargain priced at $72 EACH!

Re: Which Brand of Spark plug do you run??
 

AC Delco Platinum 41-800

Re: Which Brand of Spark plug do you run??
 

That's the one I'm going to try in mine John