Thread: Plugs

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What kind of plugs should I run in my 489 bb afr heads 649 lift cam ,I don't know if should be hot or cold or what kind

Ken, I have no idea on a specific number of plug, but the guys at AFR may be able to tell you a number to fit the heads for length of thread to get the electrode just inside the combustion chamber, not shrouded by the threaded hole but also not in too far to risk contact with a piston at high rpm. If AFR is no help then measure with a depth gauge and start going through the plug charts.
I like NGK plugs after seeing some of the horror story videos of plugs being put together in China, where most of the old line US brands are made now. I'd pick the middle of the heat range, run them for a while an take the car out for a cruise, pull a few plugs and read the color. Adjust the heat range to get the best burn pattern on your plugs after a long highway cruise, or after a few high speed passes shutting down and reading plugs before idling back to base.

Just my $0.02 and others may tell you different.

Roger is quite right, I've never had any luck with NGK's. I'm running E-3's in the Dakota and the Vette and so far so good. The heat range as Roger stated you'll have to determine probably by trial and error.