Spark Plug Heat Ranges
Road Warrior
Joined: May 2010
Posts: 1,348
Likes: 52
From: Central Illinois
I'm going to give the autolite 4163's a try.
Last year I used some NGK DCPR7E's. Did some data runs with TTS and the knock detector was going nuts. Same day, switched back to the stock plugs, did the exact same run and no knock detection.
Last year I used some NGK DCPR7E's. Did some data runs with TTS and the knock detector was going nuts. Same day, switched back to the stock plugs, did the exact same run and no knock detection.
Cruiser
Joined: Apr 2010
Posts: 171
Likes: 0
I use to drag race with a big block chevy and ran a ton of NOS. I would run differant heat range plugs and differant gaps to make all 8 cyl as close as posible. I did same thing on my 10 WG I am running the NGK Iridiums front one step colder at 35 and rear at 50. The front was to lean with stock plug and pinging and now no ping and runs a little cooler and revs a little faster. I watched a you tube video of a guy dyno a Harley and change to NGKs and it made 3 more h.p.
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Road Captain
Joined: May 2010
Posts: 636
Likes: 1
From: Monterey, CA
Wow, of all the things I found, since all my stuff has been shipped off. I still have my original spark plugs. I think someone earlier may be onto something about running two different plugs. I have one plug that is a very nice light brown and the other plug has a white deposit build-up, almost a blistered electrode look. I think the later plug was from the aft cylinder, I failed to mark them. Maybe a stock plug up front and a cooler plug in the aft cylinder. When I get home tonight, I will take some pics of the plugs and post them.
Cale
Cale
Stellar HDF Member
Joined: Sep 2007
Posts: 2,458
Likes: 671
From: Vancouver Island B.C.
Correct. The wrong resistance plug can creat havoc for the ion sening as it relies on the correct voltage. It will not hurt your engine but it causes "false knock retard" which will pull up to 8 degrees of timing. Over time the adaptive knock retard table will remove most of the timing. Only thing that will happen is your bike could loose some responsiveness and "may" see increased engine temps. Vrod plug is one step colder.
Outstanding HDF Member
Joined: Jan 2010
Posts: 2,916
Likes: 31
From: earth
Wow, of all the things I found, since all my stuff has been shipped off. I still have my original spark plugs. I think someone earlier may be onto something about running two different plugs. I have one plug that is a very nice light brown and the other plug has a white deposit build-up, almost a blistered electrode look. I think the later plug was from the aft cylinder, I failed to mark them. Maybe a stock plug up front and a cooler plug in the aft cylinder. When I get home tonight, I will take some pics of the plugs and post them.
Cale
Cale
Extreme HDF Member
Joined: Sep 2005
Posts: 11,615
Likes: 50
From: Baton Rouge, LA
Let me know how the Autolites work for you. I'm running HD Gold now, mostly because I had trouble with the screw cap on the Autolites that I mentioned earlier. When I ran the Autolites I had no way to check knock retard, but I do now with the Power Vision. I can say that at that time I was setting the advance in the cruise range by ear, and knock retard was working. If I went back to the Autolite I would probably solder the caps on.
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Road Captain
Joined: May 2010
Posts: 636
Likes: 1
From: Monterey, CA
I tried to take pics of my plugs last night, it was a no-go. When I get home next week, I can use our nice camera with a macro lens to take some real nice close-ups.
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Seasoned HDF Member
Joined: Mar 2010
Posts: 38,528
Likes: 6,407
From: Honah Lee
Probably just the grade of fuel. Regular plugs and midgrad in the states should work. Premimum if you drive it hard with two up which looks like you would. And thanks and welcome back.
Last edited by Jackie Paper; Jun 20, 2011 at 10:54 PM.
Seasoned HDF Member
Joined: Oct 2006
Posts: 5,977
Likes: 85
From: Nevada
Let me know how the Autolites work for you. I'm running HD Gold now, mostly because I had trouble with the screw cap on the Autolites that I mentioned earlier. When I ran the Autolites I had no way to check knock retard, but I do now with the Power Vision. I can say that at that time I was setting the advance in the cruise range by ear, and knock retard was working. If I went back to the Autolite I would probably solder the caps on.
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