Spark Plug ?

[turkeybird56]

Eyeballing them? Got it. Do you use ugga duggas when tightening your lug nuts as well? 3 or 4 ugga duggas for you? I prefer 4 just to make sure. If it's Sunday, I use 5 ugga duggas. Smdh...

The electrodes aren't made out of crystalized fairy tears and crumble if you look at them. They will tolerate a feeler gauge or calibrated wire passing over them without any damage. It's almost like they are designed for that or something... Just don't be an ignorant wrench when you're doing it. Use the necessary cautions and all will be good. Again, check out Youtube sometime. They have quite the selection of videos.

HEY, not need no "stinkin" correctly gapped plugs. Put them in and hope, but when U start getting misfires, and fuel mileage in the toilet, and and, hmmmmmmmm.
I long ago learned the hard way. Got lazy, threw them AC/Delcos in my Chevy, and kept on running. Boy, I thought I misread/miswired the plugs, thought reversed a cap wire or sumthin. Guess some learn the hard way. The gap was standard GM .035. Pulled all 8, 4 were correct, the other 4 were 0.25 to 0.50, and those motors back then were not as picky unless you blueprinted system and changed out distributor etc.,.

With these micro managed computer controlled rolling gizmos, not sure if that is smart or enuf.

All IMHO, so very humble, I's a BOIRD tho.

 

[QwikKota]

I've replaced plenty of spark plugs but they were typically the $1 autolite copper plugs that are very robust. Big thick center electrode. The Iridium plugs have a tiny center electrode. A lot of these new plugs state "pre-gapped, do not gap".

 

[RamDiver]

I've replaced plenty of spark plugs but they were typically the $1 autolite copper plugs that are very robust. Big thick center electrode. The Iridium plugs have a tiny center electrode. A lot of these new plugs state "pre-gapped, do not gap".

I've been gapping plugs since the '70s in everything from lawnmowers and then cars, motorcycles, and trucks.

Why would I stop now when it's so painfully simple?

IIRC, my last motorcycle in the '80s, an FZ-750, had Iridium plugs.

During the past many decades the task of quality control has shifted from manufacturers down to the end users.

I'm not about to compromise the performance of my truck by trusting a manufacturer, shipper, distributor, courier, or parts handling monkey, especially when it's such a simple task to verify.

That makes no sense in my mind.

I trust very few humans on the face of this earth, why should I trust any package telling me not to gap?

.

 

[BenchTest]

I've replaced plenty of spark plugs but they were typically the $1 autolite copper plugs that are very robust. Big thick center electrode. The Iridium plugs have a tiny center electrode. A lot of these new plugs state "pre-gapped, do not gap".

FFS... CHECKING the gap is different than CHANGING the gap. You either 1) check and install them because they are correct out of the box, or 2) check and find one or more off and adjust them prior to installing, or 3) if you don't possess the skill/tools to adjust, return/exchange them, or 4) be careless and just put whatever in your engine. In any case, you aren't adjusting anything in the center electrode. You shouldn't be making contact with the center electrode outside of gap CHECKING. $1 Autolite plugs quit being relevant about the same time as the 1911. Sure, there are old cars/trucks that use old technology like the coppers you referenced, but not on modern production vehicles as being discussed here.

Now, who wants to go adjust their points, light up a non-filter Marlboro, and shine their old slabside iron? Yee-haw cowboys and girls.

 

[BenchTest]

I've been gapping plugs since the '70s in everything from lawnmowers and then cars, motorcycles, and trucks.

Why would I stop now when it's so painfully simple?

During the past many decades the task of quality control has shifted from manufacturers down to the end users.

I'm not about to compromise the performance of my truck by trusting a manufacturer, shipper, distributor, courier, or parts handling monkey, especially when it's such a simple task to verify.

That makes no sense in my mind.

I trust very few humans on the face of this earth, why should I trust any package telling me not to gap?

.

These two...these are the folks keeping gap checking tools relevant. It's a simple task and it's much easier to not be lazy during install than to have to troubleshoot and find out later that your lazy-assedness caused you to have to redo the job.

 

[Sherman Bird]

There is a difference between CHECKING gap and damaging the electrodes trying to adjust the gap... If the plug doesn't meet spec, exchange it with the retailer. Gap exists for a reason.

... and what IS the reason for a particular gap?

 

[BenchTest]

... and what IS the reason for a particular gap?

It prevents pregnancy.

 

[RamDiver]

... and what IS the reason for a particular gap?

A less than or more than ideal sized gap will trigger at a slightly different voltage resulting in a warmer or cooler burn temperature than desired.

Too small or too large will create a misfire condition producing a poor or incomplete ignition of the fuel/air mix.

A condition that I never want to voluntarily experience in my Hemi.

.

 

[Wild one]

A less than or more than ideal sized gap will trigger at a slightly different voltage resulting in a warmer or cooler burn temperature than desired.

Too small or too large will create a misfire condition producing a poor or incomplete ignition of the fuel/air mix.

A condition that I never want to voluntarily experience in my Hemi.

.

On paper a smaller gap will advance spark timing as it takes less coil saturation time to have enough juice to jump the gap,and the opposite happens for a larger then normal gap,and as you state the voltages are slightly differant because of the saturation time.
It's pretty common to run plug gaps of .026 to .032 thousands on boosted or nitrous applications,as the higher cylinder pressures require a smaller gap for the spark to jump so it basically doesn't blow out.
I played with gaps from .026 to .032 on my nitrous'd truck and the wifes 1320,and settled on .032" for both,as i couldn't tell any differance in eithers 1/4 mile times,but i'm also running whats considered baby shots ,70 shot on the truck and 50 shot on the car.If i was running a bigger nitrous shot,i'd probably drop down to somewhere around .028",and maybe go to 3 or more steps colder on the plugs instead of the 2 steps colder i ran in both,depending on how much nitrous is being sprayed

 

[turkeybird56]

On paper a smaller gap will advance spark timing as it takes less coil saturation time to have enough juice to jump the gap,and the opposite happens for a larger then normal gap,and as you state the voltages are slightly differant because of the saturation time.
It's pretty common to run plug gaps of .026 to .032 thousands on boosted or nitrous applications,as the higher cylinder pressures require a smaller gap for the spark to jump so it basically doesn't blow out.
I played with gaps from .026 to .032 on my nitrous'd truck and the wifes 1320,and settled on .032" for both,as i couldn't tell any differance in eithers 1/4 mile times,but i'm also running whats considered baby shots ,70 shot on the truck and 50 shot on the car.If i was running a bigger nitrous shot,i'd probably drop down to somewhere around .028",and maybe go to 3 or more steps colder on the plugs instead of the 2 steps colder i ran in both,depending on how much nitrous is being sprayed

HECK of a lot of info to tell someone, hey, ahhh "Sir", maybe you should verify the gap on the plugs before you install (sic).

 

[turkeybird56]

FFS... CHECKING the gap is different than CHANGING the gap. You either 1) check and install them because they are correct out of the box, or 2) check and find one or more off and adjust them prior to installing, or 3) if you don't possess the skill/tools to adjust, return/exchange them, or 4) be careless and just put whatever in your engine. In any case, you aren't adjusting anything in the center electrode. You shouldn't be making contact with the center electrode outside of gap CHECKING. $1 Autolite plugs quit being relevant about the same time as the 1911. Sure, there are old cars/trucks that use old technology like the coppers you referenced, but not on modern production vehicles as being discussed here.

Now, who wants to go adjust their points, light up a non-filter Marlboro, and shine their old slabside iron? Yee-haw cowboys and girls.

Used to take a matchbook cover, fold over in half, and use to adjust my points, roflmao. Works good on Chevy Big Block (us kids had no money or fancy tools back then).

ADDED: Of course if U pop the hood and are looking for points, I doubt you popped the hood on a Modern RAM truck, lol.

 

[Sherman Bird]

On paper a smaller gap will advance spark timing as it takes less coil saturation time to have enough juice to jump the gap,and the opposite happens for a larger then normal gap,and as you state the voltages are slightly differant because of the saturation time.
It's pretty common to run plug gaps of .026 to .032 thousands on boosted or nitrous applications,as the higher cylinder pressures require a smaller gap for the spark to jump so it basically doesn't blow out.
I played with gaps from .026 to .032 on my nitrous'd truck and the wifes 1320,and settled on .032" for both,as i couldn't tell any differance in eithers 1/4 mile times,but i'm also running whats considered baby shots ,70 shot on the truck and 50 shot on the car.If i was running a bigger nitrous shot,i'd probably drop down to somewhere around .028",and maybe go to 3 or more steps colder on the plugs instead of the 2 steps colder i ran in both,depending on how much nitrous is being sprayed

I've played with plug gaps, too. I used a high end DSO and looked at the secondary wave form AT the plug gap/spark line. These modern computers in cars are fascinating in that they can make up for a lot of small problems to maintain emissions that wasn't possible pre-engine control systems management. I can see "normal" secondary waves on the scope screen when the EEC is in control of fine tuning on a modern, current vehicle that absolutely goes to trash when the throttle is snapped and correction is suspended (at WOT) and see the real story of how a tiny change in gap can negatively affect ignition profile, yet the car runs fine and doesn't flag any DTC's or will flag that aggravating P0300 and no other codes.

Bottom line is that an EEC equipped car CAN correct to the point of destructive damage to an engine; thus the flashing CEL indicator to warn a driver that the ECM has detected a condition that can/will destroy either the engine or the catalytic converter.
In short, if one has a bad COP coil, the spark plug(s) are the cause the majority of the time.

 

[Wild one]

I've played with plug gaps, too. I used a high end DSO and looked at the secondary wave form AT the plug gap/spark line. These modern computers in cars are fascinating in that they can make up for a lot of small problems to maintain emissions that wasn't possible pre-engine control systems management. I can see "normal" secondary waves on the scope screen when the EEC is in control of fine tuning on a modern, current vehicle that absolutely goes to trash when the throttle is snapped and correction is suspended (at WOT) and see the real story of how a tiny change in gap can negatively affect ignition profile, yet the car runs fine and doesn't flag any DTC's or will flag that aggravating P0300 and no other codes.

Bottom line is that an EEC equipped car CAN correct to the point of destructive damage to an engine; thus the flashing CEL indicator to warn a driver that the ECM has detected a condition that can/will destroy either the engine or the catalytic converter.
In short, if one has a bad COP coil, the spark plug(s) are the cause the majority of the time.

Back in the single coil days with carburators there could be a noticable differance by adjusting the plug gaps,especially with a points ignition,but like you say with the advent of computor controlled COP engines,it's not nearly as noticable

 

[Sherman Bird]

With a distributor, the "forgotten" ignition gap is the one between the rotor and the cap terminals. When this gap becomes "dominant" i.e. larger than the plug gap, per se, there WILL be secondary mayhem (misfires). Look at the GM "Vortec" V-6 and V-8 engines with a distributor. Although they function in the classic way, they no longer provide the ignition toggle. THAT is accomplished by a crank position sensor at the front of the crank in the timing cover, thus, base timing is fixed. Don't believe me? Try hooking up a timing light on the "R" engine (350 Vortec v-8) and watching the timing mark on the balancer as you move the distributor. All you accomplish there is making the KV demand shoot out the roof at that airgap inside the distributor. That's why one has to set that type of distributor with a scanner reading the PID for CMP and setting that to ZERO +- 2 degrees to keep the Check engine light off.

Eventually that dinosaur went extinct, and gave way to COP systems.

 

[ppine]

spark plugs? Negative.

 

[RamDiver]

On paper a smaller gap will advance spark timing as it takes less coil saturation time to have enough juice to jump the gap,and the opposite happens for a larger then normal gap,and as you state the voltages are slightly differant because of the saturation time.
It's pretty common to run plug gaps of .026 to .032 thousands on boosted or nitrous applications,as the higher cylinder pressures require a smaller gap for the spark to jump so it basically doesn't blow out.
I played with gaps from .026 to .032 on my nitrous'd truck and the wifes 1320,and settled on .032" for both,as i couldn't tell any differance in eithers 1/4 mile times,but i'm also running whats considered baby shots ,70 shot on the truck and 50 shot on the car.If i was running a bigger nitrous shot,i'd probably drop down to somewhere around .028",and maybe go to 3 or more steps colder on the plugs instead of the 2 steps colder i ran in both,depending on how much nitrous is being sprayed

Yes, thanks for the additional timing references.

I would expect the physics behind gapping plugs and timing to go beyond theory or 'on paper'.

I had written about how a smaller gap would trigger at a lower voltage and advance the timing.
A larger gap would conversely require a higher voltage and ret ard the timing but then deleted it thinking someone with more experience like yourself would chime in soon.

Although I've been gapping plugs since the '70s, my only experience of gapping for performance was on motorcycles in the '80s primarily on my FZ-750.

The Yamaha Genesis engine from 1985 was an incredible feat of engineering that was very fast as a stock machine, but it was also simple to increase the performance with a few tweaks.

I don't know if my license would have survived me keeping that machine but, I sure regret selling it.

We heard the same hyperbole back then about not adjusting gaps on plugs but quickly laughed it off.

Back to the Hemi, I would expect the timing to be more critical with 2 plugs per cylinder.
I'm curious to learn about the timing used for the detonation plugs versus exhaust plugs and if you were tweaking that relationship to optimize performance while running Nitrous.




I just realized that picture was taken before I added the Vance & Hynes exhaust and a pile of other performance tweaks. This was likely taken in '86 or '87.

.

 

[Sherman Bird]

All modern OBD2 engine control systems have ONE primary mission, and many subroutine tasks to achieve said mission: 1.0 LAMBDA. (AKA 14.7 to 1 air/fuel ratio). Spark plug gaps, spark plug heat range, resistance built into the plugs, are all part of the equation to reach this goal.

 

[Alweeja]

Are NGK Th e Best Option.....why?

 

[NCRaineman]

Are NGK Th e Best Option.....why?

NGK has been recognized as superior plugs for many years. What magic makes them better than the competition? Don't know, but they're what performance enthusiasts swear by.

 

[Shawn Burns]

How to Gap Iridium Spark Plugs

Who says you can't gap iridium? You just need the right tools!Please keep in mind that I'm not a professional mechanic and no video can replace proper experi...

www.youtube.com

I would recommend using a spark plug gap tool, rather than the method used in the video. Especially, if you aren't an experienced mechanic.

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