Best spark plugs?
Road Master
Joined: Dec 2009
Posts: 1,223
Likes: 6
From: Las Vegas, NV
Agree with the rest here......unless you have a seriously built motor....stock plugs are best.
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Extreme HDF Member
Joined: Sep 2006
Posts: 10,033
Likes: 29
HD Platinums work best in my 2000.
At 6500 miles, I got a miss on the stock plugs. I put in another set. I got the same results in about the same amount of miles. Then, I put in HD Platinums. I ran those 30k before swapping them out. I only swapped them because I had just put in new cams and a DFO and wanted to monitor my plug condition. That set of plugs now has 25k on it and are still running strong.
At 6500 miles, I got a miss on the stock plugs. I put in another set. I got the same results in about the same amount of miles. Then, I put in HD Platinums. I ran those 30k before swapping them out. I only swapped them because I had just put in new cams and a DFO and wanted to monitor my plug condition. That set of plugs now has 25k on it and are still running strong.
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Tourer
Joined: Jun 2009
Posts: 424
Likes: 2
From: Middle of Kansas
I must have had a bad run of HD plugs!
I had 2 quit firing in one year(different cylinders) and 1 new out of the box that was weak.
After a few hours troubleshooting the ignition and everything else,I pulled a pair of used Autolites out of my Jeep 304(same plug) and it ran fine!
That was a few years ago but I've been running Autolites since then with no issues.
I had 2 quit firing in one year(different cylinders) and 1 new out of the box that was weak.
After a few hours troubleshooting the ignition and everything else,I pulled a pair of used Autolites out of my Jeep 304(same plug) and it ran fine!
That was a few years ago but I've been running Autolites since then with no issues.
