Spark Plugs

[Princess Valiant]

who can explain spark plugs in detail?

I have overheard conversations where guys are talking about "hotter or colder" plug ....I never say anything because I don't know what that means.

I want to know everything about spark plugs so who can explain??

 

[Oklacarcollecto]

Here is a good 5 page article from NGK that popped up in a Google search.

http://www.ngksparkplugs.com/tech_support/spark_plugs/index.asp?mode=nml

 

[Princess Valiant]

so then, according to that video ...spark plugs play a bigger role than many know.

if the heat range can cause pre-ignition then it is just as important as timing and octane ratings.......?

so how would spark plugs be effected by unleaded fuel ....when our cars were new, most ran on leaded fuel and now that is no where near the case......i would think new fuels run hotter, so would we need colder plugs?

also what about altitiude?

and what about seasons? during cold weather would one plug work better than another?

 

[Oklacarcollecto]

Here is some other articles that may interest you.

http://yosemite.epa.gov/R10/airpage.nsf/webpage/Leaded+Gas+Phaseout


[ame]http://www.ngksparkplugs.com/docs/tech/racing_spark_plugs_performance_applications.pdf[/ame]

 

[Oklacarcollecto]

What Factors Affect Spark-Plug Heat Range?


http://www.hotrod.com/techarticles/hrdp_1303_what_factors_affect_spark_plug_heat_range/

 

[Oklacarcollecto]

This is a Notorn motorcycle thread but it even touches on chemistry and the fact we had unleaded first.

Leaded, unleaded, and a bit of history


Once upon a time all petrol was unleaded - surprised?

http://www.nortonownersclub.org/support/technical-support-general/leaded-unleaded

 

[Oklacarcollecto]

Here is a bunch of threads here on FABO that I found by searching "spark plug heat range"

http://www.forabodiesonly.com/mopar/search.php?searchid=7042165

 

[inkjunkie]

Old time drag racers will often talk about indexing them....getting them oriented in the head so that the end electrode is towards the combustion chamber....Drag racer I helped years ago and I would sit in his basement, chugging beers indexing plugs for the up coming season. We put new plugs in the car every 15 passes or so....

 

[67Dart273]

The simple answer is that a colder plug has a shorter tip and therefore conducts heat away from the tip faster than a "hot" plug

You cannot compare plug numbers in different series plugs, that is, the numbers are somewhat arbitrary. So as example the older /6 engines used a different plug than the newer "peanut plug" heads. Some engines (in Champion, example) might accidently come up with the same heat range number

You have to be careful because let's say you have an engine that is actually running lean, that is, not enough fuel. You might INcorrectly conclude that "it needs" a colder plug because they are looking so "hot" when in fact what you really need to do is richen it up.

This is why the wideband O2 setups have become so popular. You cannot really tell what an engine is doing simply by looking at the plugs.

 

[Princess Valiant]

so then why do some have multiple ground electrodes and most only have one .....and what does platinum mean?

 

[67Dart273]

Platinum, unless "they are lying" should give you superior electrode life.


Plugs have experimentally, and somewhat successfully, been made of "all sorts" of materials over the years............some was good and some was just BS. Some designs with multiple electrodes are BS in my book. You have to ask yourself, "if this design" is so good, why aren't ALL plug makers doing so?

One story concerns the 60's I guess when "someone discovered" that sometimes putting a GAP in series with the spark actually makes it "more intense." Champion plugs came out with their "booster gap" plugs

and AC/ Delco came out with a SHORTER rotor for the popular GM V8 distributors which pretty much made the Champion plugs irrelevant.

You could also buy "add on" boosters that went into the center of the coil tower,

I guess what I'm trying to get at is, there's been all kinds of "doo dads" over the years, some not so "helpful."

At least one was the infamous "J.C. Whitney" (Warshosky) "Lifetime fire injectors"

http://people.ucalgary.ca/~csimpson/Articles/GMiser.html

The latest I'm aware of is these "E3" things, and frankly........

you-are-gonna-havta-prove-it-to-me

 

[RustyRatRod]

The E3's are bullshit. I had them in my 08 Jeep and they threw misfire codes comin and goin. I put the champions back in and they were fine.

 

[64DartGTinAZ]

so then why do some have multiple ground electrodes and most only have one

Marketing...kind of like Nigel Tufnel's amps going to 11.

 

[Princess Valiant]

why are some spark plugs a 5/8 inch socket size and some are bigger .....does the size of socket it fits into mean anything?

 

[Oklacarcollecto]

why are some spark plugs a 5/8 inch socket size and some are bigger .....does the size of socket it fits into mean anything?

They even used to be bigger than 13/16 and you could actually remove the ceramic core on the early ones. I have some NOS AC plugs that are so old the only identification on them is the letter C.

 

[67Dart273]

Socket size is just the design. The plugs for our old Farmall tractor took a 7/8 wrench.

When I was 4-5 years old, I severely cut my hand, needing several stitches. My Dad was out in the old shed, working on something, and I'd been pestering him. So he took a plug ---some of them came apart back then.......and pointed me to the vise and a crescent wrench.

I was having fun taking that plug apart and putting it back together when the wrench slipped --- I fell backwards, --- and cut the heck out of my had as I fell against the very sharp double bit axe leaning on the back wall.

Down to the doc..........stitches.

Probably like these -- fits Model A Ford or model T. These appear to be pipe (tapered) thread.

There was all kinds of quirks and gadgets ........one of these has a fuel priming cup

http://4.bp.blogspot.com/-A-iKomeyq3Q/TpE_L2rfzbI/AAAAAAABq20/Pvn1N5zvpRI/s1600/DSC_0039.JPG

Some aircraft use fully shielded plugs -- for radio noise suppression. The wires and connectors work "sort of" like RF coaxial cable-- a wire in a dielectric, inside a metal braided shield. These were also somewhat waterproof and were used in some Jeeps and other land vehicles for fording streams

I've got one of these, a "spark plug whistle."

http://www.mtfca.com/discus/messages/118802/150236.jpg

and lest not forget, "spark plug tire pump"

 

[daredevil]

Platinum, unless "they are lying" should give you superior electrode life.


Plugs have experimentally, and somewhat successfully, been made of "all sorts" of materials over the years............some was good and some was just BS. Some designs with multiple electrodes are BS in my book. You have to ask yourself, "if this design" is so good, why aren't ALL plug makers doing so?

One story concerns the 60's I guess when "someone discovered" that sometimes putting a GAP in series with the spark actually makes it "more intense." Champion plugs came out with their "booster gap" plugs

and AC/ Delco came out with a SHORTER rotor for the popular GM V8 distributors which pretty much made the Champion plugs irrelevant.

You could also buy "add on" boosters that went into the center of the coil tower,

I guess what I'm trying to get at is, there's been all kinds of "doo dads" over the years, some not so "helpful."

At least one was the infamous "J.C. Whitney" (Warshosky) "Lifetime fire injectors"

http://people.ucalgary.ca/~csimpson/Articles/GMiser.html

The latest I'm aware of is these "E3" things, and frankly........

you-are-gonna-havta-prove-it-to-me

The added gap works. 2 stroke dirt bikes foul plugs and you can clean them up by pulling the boot off a little. Used to work on my 750 h2

 

[4spdragtop]

I dunno if stated or not in here, I noticed there were some NGK links posted, but here is a link I started the other day with a heat range chart from NGK.

http://www.forabodiesonly.com/mopar/showthread.php?t=251160

 

[3406pk]

For moderators, this would be a good sticky topic.