Quantcast Some Spark Plug Info - Ford Truck Club Forum




Home






Forum






Gallery






Garage






Blog






Arcade






Settings






New Posts






TOTM






Vote




Remember Me?
       Join for free!




Search






How-To's






Unanswered






FTC Toolbar






Social Sites






Register




 
Ford Truck Club Forum > GARAGE TALK > Garage Talk: Shop Class 101



Welcome to FordTruckClub.net
Welcome to FordTruckClub.net, the internet's premier Ford truck community! You are currently viewing our boards as a guest which gives you limited access to view discussions and access other forum features. By joining our free online community you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is fast, simple, and absolutely free so please, join our community today!

Forgot your password? click here.

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 

 
Thread Tools Search this Thread Display Modes
  #1  
Old January 15th, 2013, 09:24 PM
JSoko's Avatar
JSoko JSoko is offline

 

Join Date: Jun 2009
Location: Northwest Georgia
Posts: 15,010
Images: 629
Likes : 34
Liked 187 Times in 169 Posts
Lightbulb Some Spark Plug Info

On my Harley site; I was asked what spark plug I use in my 1948 Harley
and here's some Q&A

[Quote:
Originally Posted by jsoko
I use AutoLite plugs @ .040 and I file the ground strap & indexed; other plugs I've tried all seem to foul; I run an S&S Super E Carb: Quote]

[Quote:
Originally Posted by Panman
Why do you file the ground strap. That seems to go against what I think i know about electrical theory; and what is indexed mean, Educate me.:Quote]

[Quote:
Originally Posted by jsoko
Filing & Indexing

Filing - is a technique that the Pro Stock and NASCAR guys have used for years, and now the spark plug manufacturers make the plugs this way for them. Filing - the ground electrode is filed/cut back until even with the outside edge of the center electrode. The benefit of this is to unshroud the flame kernel to the combustion chamber. Filing off the sharp edges will help fight off detonation/pining some! It's often overlooked!

Indexing - is positioning the spark plug so the open end is facing toward the intake valve, this can be achieved by more or less torque on a new washer or by using washers which can be had in different thickness for this reason. Indexing lets the flame kernel point toward the incoming fuel charge for best combustion. These are a few things that when added to other performance enhancers lets my old Bike leave the new ones behind. This is a must on forced induction.
I learned this from my Dad many moons ago.

but none of this really doesn't matter near as much as my timing and curve.



__________________

Here's More;

I have been asked many times to explane 'Heat Range';... So Here's what I got


Spark plugs are one of the biggest "Gimmicks" on the market. What I mean by that is there are dozens of bullshit marketing reasons to get you to spend more money on something you don't need.

Spark plugs are one of the most misunderstood components of an engine. Numerous questions have surfaced over the years, leaving many folks confused.

Spark plugs are the "window" into your engine (your only eyewitness to the combustion chamber), and can be used as a valuable diagnostic tool. The spark plug displays symptoms and conditions of the engine's performance. The experienced tuner can analyze these symptoms to track down the root cause of many problems, or to determine air/fuel ratios (to a degree).


SPARK PLUG BASICS:
The spark plug has two primary functions:

1/ To ignite the air/fuel mixture

2/ To remove heat from the combustion chamber (this is something confusing to a lot of folks )


Spark plugs transmit electrical energy that turns fuel into working energy. A sufficient amount of voltage must be supplied by the ignition system to cause it to spark across the spark plug's gap. This is called "Electrical Performance."

The temperature of the spark plug's firing end must be kept low enough to prevent pre-ignition, but high enough to prevent fouling. This is called "Thermal Performance", and is determined by the heat range selected.

NOTE: It is important to remember that spark plugs do not create heat, they can only remove heat. The spark plug works as a heat exchanger by pulling unwanted thermal energy away from the combustion chamber, and transferring the heat to the engine's cooling system. The heat range is defined as a plug's ability to dissipate heat. This is sometrhing I late came to appreciate during my Mechanical Engineering training.



Understanding what a heat range is:


A spark plug's heat range has no relationship to the actual voltage transferred though the spark plug. It will not increase engine torque or horsepower. The heat range is a measure of the spark plug's ability to remove heat from the combustion chamber in order to burn carbon deposits off of it's electrode (clean itself). The heat range measurement is determined by several factors; the length of the ceramic center insulator nose and its' ability to absorb and transfer combustion heat, the material composition of the insulator and center electrode material.


* The insulator nose length
* Gas volume around the insulator nose
* The materials/construction of the center electrode and porcelain insulator


The insulator nose length is the distance from the firing tip of the insulator to the point where insulator meets the metal shell. Since the insulator tip is the hottest part of the spark plug, the tip temperature is a primary factor in pre-ignition and fouling. Whether the spark plugs are fitted in a lawnmower, boat, or a race car, the spark plug tip temperature must remain between 932°F-1562°F. If the tip temperature is lower than 932°F, the insulator area surrounding the center electrode will not be hot enough to burn off carbon and combustion chamber deposits. These accumulated deposits can result in spark plug fouling leading to misfire. If the tip temperature is higher than 1562°F the spark plug will overheat which may cause the ceramic around the center electrode to blister and the electrodes to melt. This may lead to pre-ignition /detonation and expensive engine damage. In identical spark plug types, the difference from one heat range to the next is the ability to remove approximately 158°F to 212°F from the combustion chamber.



The firing end appearance also depends on the spark plug tip temperature. There are three basic diagnostic criteria for spark plugs: good, fouled and overheated. The borderline between the fouling and optimum operating regions is called the spark plug self-cleaning temperature. The temperature at this point is where the accumulated carbon and combustion deposits are burned off.

Keeping in mind that the insulator nose length is a determining factor in the heat range of a spark plug, the longer the insulator nose, the less heat is absorbed, and the further the heat must travel into the cylinder head and to the cooling fins. This means the plug has a higher internal temperature, and is said to be a hot plug. A hot spark plug maintains a higher internal operating temperature to burn off oil and carbon deposits, and has no relationship to spark quality or intensity.

Conversely, a cold spark plug has a shorter insulator nose and absorbs more combustion chamber heat. This heat travels a shorter distance, and allows the plug to operate at a lower internal temperature. A colder heat range is necessary when the engine is modified for performance, subjected to heavy loads, or is run at high rpms for a significant period of time. The colder type removes heat more quickly, and will reduce the chance of pre-ignition/detonation and melting or damage to the firing end. (Engine temperature can affect the spark plug's operating temperature, but not the spark plugs heat range).

I remember from a long time ago (teenager) when buying plugs for my Harley, the service guy asked me if I was riding around town or going on a highway trip; this as a confuseing question then he proceded to explane and since that time I have explaned the insulator theory to others. On preformance engines how you use or stay at a certian RPM will determine wether to use a HOT or COLD plug.



For Those Who Fought For It...
Freedom Has A Taste The Protected Will Never Know.













Last edited by JSoko; January 16th, 2013 at 10:25 AM.
  #2  
Old January 15th, 2013, 09:48 PM
BigBlue79's Avatar
BigBlue79 BigBlue79 is offline
 

Join Date: Sep 2011
Location: Sapulpa, OK
Posts: 5,892
Images: 1113
Likes : 14
Liked 51 Times in 44 Posts
Default

J, got any pictures for us about filing the ground?
  #3  
Old January 15th, 2013, 09:52 PM
JSoko's Avatar
JSoko JSoko is offline

 

Join Date: Jun 2009
Location: Northwest Georgia
Posts: 15,010
Images: 629
Likes : 34
Liked 187 Times in 169 Posts
Default

I could go out to the shop and take one but not tonight
what you do is just file the ground strap down even with the edge of the vertical electrode, got the mental picture now

I'll post a before & after plug pic tomorrow


For Those Who Fought For It...
Freedom Has A Taste The Protected Will Never Know.












  #4  
Old January 15th, 2013, 09:58 PM
BigBlue79's Avatar
BigBlue79 BigBlue79 is offline
 

Join Date: Sep 2011
Location: Sapulpa, OK
Posts: 5,892
Images: 1113
Likes : 14
Liked 51 Times in 44 Posts
Default

Yep, I think I've got it, wonder what benefits, if any, it'd have on a V8 engine.
  #5  
Old January 15th, 2013, 10:19 PM
JSoko's Avatar
JSoko JSoko is offline

 

Join Date: Jun 2009
Location: Northwest Georgia
Posts: 15,010
Images: 629
Likes : 34
Liked 187 Times in 169 Posts
Default

we dont just do it on Harleys, remember what i said "NASCAR & Pro Stock"

Dad always had fast cars and I remember when I was a kid working on my cars doing stuff like this and folks saying i was crazy "that don't do no good it's a waste of time"
on the weekends it was a different tune

with a carb, points, plugs, a few wires and a battery; you had to use every advantage you could come up with, and Dad knew some of the best engine builders in North Georgia that always had a trick up their sleeve


For Those Who Fought For It...
Freedom Has A Taste The Protected Will Never Know.













Last edited by JSoko; January 16th, 2013 at 10:27 AM.
  #6  
Old January 16th, 2013, 10:15 AM
JSoko's Avatar
JSoko JSoko is offline

 

Join Date: Jun 2009
Location: Northwest Georgia
Posts: 15,010
Images: 629
Likes : 34
Liked 187 Times in 169 Posts
Default

here's what a teacher at the Harley school had to say

[Quote:
Originally posted by choppers

If you have points or a stock ignition precious metal plugs like a Bosch Platinum or an Autolit Irridium may help as the precious metals are more conductive and will provide a quicker path to the spark. Since it gets there a micro second quicker you "may" have a bit of a longer spark.
If you have a high energy ignition you are likely better off with standard plugs as the higher resistance will provide a longer and wider spark than the stock set up.
I like the standard Autolites.
Incidentally, the multi pronged plugs like the Bosch four prongers is a gimmick, contrary to their advertisement. We tested dozens of different types of plugs at school and most of these simply made the spark bounce around from prong to prong. The ones with the "V" tip were really bad. They all had a hot and localized/centered spark. Likely to burn a hole in a piston.:Quote]


For Those Who Fought For It...
Freedom Has A Taste The Protected Will Never Know.












  #7  
Old January 16th, 2013, 02:06 PM
JSoko's Avatar
JSoko JSoko is offline

 

Join Date: Jun 2009
Location: Northwest Georgia
Posts: 15,010
Images: 629
Likes : 34
Liked 187 Times in 169 Posts
Default

Quote:
Originally Posted by BigBlue79 View Post
J, got any pictures for us about filing the ground?
here, the best of 8 close-up photos

the plug on the left is fresh out of the box,
the plug on the right has been filed and the ground strap has been reshaped to form a right angle to the electrode.




For Those Who Fought For It...
Freedom Has A Taste The Protected Will Never Know.












  #8  
Old January 16th, 2013, 05:48 PM
BigBlue79's Avatar
BigBlue79 BigBlue79 is offline
 

Join Date: Sep 2011
Location: Sapulpa, OK
Posts: 5,892
Images: 1113
Likes : 14
Liked 51 Times in 44 Posts
Default

So basically all we're doing is filing the ground strap to match the width of the electrode and then re-shaping a bit to form a better angle for the spark to jump. I'm going to have to try this.

I've also noticed that on my bronco, running an Accel Brass Cap and Rotor kit, BWD 8mm HEI wires, stock coil, and Bosch Copper's it likes to pre-ignite a bit when I get the plugs for a 351w, now when I had the Platinum's in there for a 400 believe it or not it ran better, IIRC it was one heat range hotter, so I might try those again. Course I've also got some more tuning to do..


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes


(View-All Members who have read this thread : 8
BigBlue79 , Bluegillfisher , countrytruck , glc , JSoko , Klitch , nydon , Russo2

Similar Threads
Thread Thread Starter Forum Replies Last Post
How to Spark Plug Wires JSoko Garage Talk: Shop Class 101 24 December 15th, 2011 02:04 AM
How to replace spark plug wires JSoko Garage Talk: Shop Class 101 4 March 16th, 2011 09:09 AM
NEW '04-'08 Spark Plug; 4.6 & 5.4 3V JSoko 2004-2008 Ford F150
13 July 15th, 2010 09:59 PM
04-05 Spark Plug Problem 2004FX4F150 Garage Talk: Paint & Detailing 3 March 10th, 2010 03:35 PM
5.4 Spark Plug Socket JSoko Garage Talk: The Tool Depot™ 0 July 18th, 2009 01:06 PM

Tags
info , plug , spark

Forum Jump









FordTruckClub.net is not authorized, endorsed or affiliated with the Ford Motor Company
or any of their subsidiaries. Ford® is a registered trademark of the Ford Motor Company


Powered by vBulletin® Version 3.8.6 Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.