spark plugs?
Supporter
Joined: Aug 2008
Posts: 5,189
Likes: 16
From: N.E. Wisconsin
Autolite 4164 or stock 6R12 every 2 or 3 yrs.
Here is a cross ref. chart.
http://www.harley-performance.com/ha...park-plug.html
Here is a cross ref. chart.
http://www.harley-performance.com/ha...park-plug.html
Road Master
Joined: Apr 2012
Posts: 1,096
Likes: 17
From: San Jose
The only difference I see is the SE plugs have a better fit to the boots on the SE wires. I put SE wires because I wanted red wires, then I noticed the boot was loose on the plug so I figured I would see if the SE plugs fit better, they did.
Extreme HDF Member
Joined: Sep 2010
Posts: 14,744
Likes: 402
From: Phoenix '53, '88, '09 Big Twins
i stick with the stock hd plugs for one reason. the ecm requires your spark plugs to be a certain ohm rating in order for the knock sensor to work properly. other plugs may fit, and they may or may not have the correct resistance. i know the stock hd plugs do. it isn't like you have to change them with every oil change anyway so to spend a couple extra bucks on the hd badge is no big deal.....
IF your model's computer uses data from the plugs and wires for "ion sense", a plug or wire change may cause reduced performance...even screaming eagle stuff. IF the computer think that the motor is knocking or pinging, if may retard timing= reduced performance
oem stuff is fine.
plugs mattered more when ignition systems and fuel systems were less precise...a "great plug" could burn it's way through fuel mixtures which might foul a regular plug. ( like my old Panhead- i use platinum plugs)
2.) auto manufacturers need to squeeze the best MPG they can to meet CAFE standards, they also want to get best power for bragging rights ( both of these are mentioned in every car commercial I see).
- If using an E3, splitfire*, or magic plug provided these advantages, wouldn't GM, Ford and Fiat use them?
as above, these magic plugs will often 'win" in a test where the fuel delivery or ignition system is not performing at it's best.
mike
* here is where splitfire paid a fine for deceptive claims in 1997:
http://www.ftc.gov/news-events/press...ncy-claims-are
Last edited by mkguitar; Jan 12, 2014 at 11:46 PM.
Cruiser
Joined: Feb 2013
Posts: 153
Likes: 0
From: Ventura Co.
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Road Warrior
Joined: Dec 2012
Posts: 1,335
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From: CT
Part number please...