Should I scramble to horde Champion J13Ys now that I have an Edelbrock 1405?

Gerald Morris

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Greetings Moparians!

Have been testing the newly rebuilt 915 heads with Edelbrock 1405 on our quarter million mile 383. The old motor purrs around town streets nicely enough, but I see when putting it on the interstate a creeping rise in temperature that I don't care for. I can think of a number of possible causes of this nastiness, not the least being the new carburetor's secondaries getting too little petrol to the jets, but I also see that 4 barrel 383s in Slab Side Land ran the J13Y, not the J14Ys I've successfully horded. I have a FEW J13Ys, as I tried using them a few years ago, but thought I'd ask the More Knowledgeable if bumping plug heat down one notch is mandatory for the new setup or not. I notice that I'll need to recurve or replace the distributor(s) I've got for this new 4 barrel universe we're entering too.

I decided to do this several years ago, as many of you know, because its difficult to obtain NEW 2 barrel carburetors for our B/RB engines, and frankly, the rebuilt ones suck! (air, mostly, where they shouldn't, though throttle plates also get diddled over the decades, and so forth...) I finally got the BBD to run the pre-improved engine, by doing an absurdly unbalanced setting of one idle jet almost falling out of the carburetor base, while the other was open just slightly more than ONE TURN from closed. The engine ran, idled and did as well as an old motor with fully half its exhaust valves not sealing well could. I'll upload a pic of the old heads in the other thread soon, for the Curious.

I see few reputable plug companies exist IN the U.S. any longer, or anyWHERE apparently. I might embrace NGK, as I THINK they at least still run their stuff from Japan? I'll check that too.

Anyway, is it worth grabbing J13Y plugs or not right now?
 

CBODY67

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The '72 400 2bbl had J-13Ys rather than the prior J-14Ys of the '66 Newport 383 2bbl. Almost all of the old 383 4bbls spec'd J-12Y or J-10Ys. To me, the 10s should be too cold for normal driving, but they had to tolerate long police chase situations, too. So "cold" it was. Even some J-9Ys in the earlier 1960s, IIRC.

From my experiences, "creeping heat" at freeway speeds is not a spark plug heat range issue. But might be an ignition timing issue, sometimes. If the mixture might be causing the heat issue, there should be other performance issues at play, too. But unless the secondaries are open through all of this, their jetting should not be an issue.

NGK Iridiums are re-packaged OEM with GM and Ford. Probably Chrysler too? With their fine-wire electrodes, the ground electrode will not shade the flame kernel as it expands. There are some YouTube videos showing a "big bang" when the spark happens with them, vs normal-configuration spark plugs.

There are a few ways to modify normal spark plugs' ground electrodes, though, to approximate that "big bang", though.

CBODY67
 

Loadrunner

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I personally quit using Champion plugs automotively quite a long time ago, decades, but will still use them in small equipment, J8, which is an old non resistor plug.

They are still the plug of choice for small aircraft, although a separate division, with the necessary quality control.

Back in 1978, I worked as a grunt for AAMCO Transmissions, moving transmissions and protecting the boss from angry customers. The boss, "Dick" was a former airplane mechanic who's favorite line was "I never had one comeback in 20 years", it usually took people a minute to get it ;]

I much prefer NGK these days and have been running them in Mopars for years, as well as some AC Delco plugs, but look for older Made in the USA packaging, later Mexico, still ok, China is a no for me.

Autolites went China years ago, not that I cared much.

NGK are not all Japan made anymore, some Brazil production for years now.


I'm personally adamant about sticking with $1.99 Copper plugs, now $2.99, versus the endless crop of fancy spark plugs.

This is some anecdotal evidence about some fancy platinum or iridium tip plugs;

I got talked into buying a set of 4 fancy NGK's for wife's Impreza by counterguy who claimed something like "5 more miles to the gallon", so I installed them as part of a fall tune up.

Wife goes out there at some point that winter, comes back in house and say "car won't start".

Being a man, I figured she was doing it wrong, ha... so I went out there for the same experience. No light, no joy.

On a well educated hunch - I lived through the Splitfire gimmick era, and they were told by a court to stop making claims about their plugs - I pulled the fancy plugs out, which were wet, reinstalled the old plain jane BKR6 plugs - that I'd saved - back in and the car lit right up.

You shoulda seen the look on the counterguy's face when I made him take those back.

NGK coppers for me, in everything.
 
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volksworld

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heat range has always been a balancing act...performance applications want cold plugs so the electrodes don't remain so hot as to cause preignition (lighting the mixture before the spark can)...however a cold plug can foul easily...so "normal" operation would want the electrodes to stay hot enough to burn off deposits from extended idling at rich fuel mixtures and/or oil burning...so you may have to play around with a couple different ranges to see where your particular combo is happiest...the '' best'' plug for your carb/cam/compression/advance may not play well with 250K rings...
 
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Loadrunner

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Racing plugs would surely foul in traffic.

In this age of modernity, it's prob not difficult to get some Air/Fuel ratio readings in the cab.

Lean = better emissions maybe, but also heat, so make sure that the mixture is adequately "fat" at cruising ranges by letting a little more fuel through, usually a metering rod job.

Did it all by seat of the pants in the old days, but the temp gauge, if it is not lying, is something to keep an eye on, it should be in the middle of the range, ideally.
 

70bigblockdodge

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My 2 cents is..... For the driving you do (around town, stop and go) and not having a high speed misfire I would just run the 14s you already own.
Personally I agree with loadrunner and stopped using those lawnmower plugs years ago.
NGK are my current favorite although in the interest of cheapness I do run autolites in daily 440 and 400
Those 1400 Eddy's seem to run lean so that's where I would look for temp creep first also advance make sure you have enough at cruise.
 

CBODY67

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Back in the later 1960s, when I started paying attention to spark plugs, I found a then-new Petersen Publications book on ignition systems at the newsstand. It had lots of Champion references in it. One thing that got my attention, really a few others too, was their "J-Gap" racing plugs. Having the ground electrode only cover 1/2 of the center electrode took less energy to fire and made for a better spark. At a time when it was normal for the ground electrode to completely cover the center electrode.

So one warm Sunday afternoon, I took the plugs out of the then-used-car '66 Newport 383 for a look and re-gap of the OEM Champion J-14Y plugs. I spent hours filing those ground electrodes back to mimic the J-Gap orientation. When done, I could tell that off-idle throttle response was a bit sharper. I smiled. Much later, I used a pair of sharp diagnoal cutters to do the shortening with, then filled things flat, smooth, and sharp with my trusty points file. In more recent times, I tried taking a pair of pliers and gently twisting the ground electrode so it only covered 1/2 of the center electrode. Seemed to work almost as well on my lawnmower engines as the "Quick-Start" lawn mower spark plugs Champion sells.

This was also during the times (middle 1960s) when Champion claimed their spark plugs ran better than other brands, using two Cadillacs with electronic throttle controls at the drag strip. As things later evolved, they were using their "Commercial" plugs rather than their normal OEM plugs. The "Commercial" plugs had an internal air gap the spark had to jump before it got to the spark plug tip. Which meant the coil had to generate more power to jump the two gaps.

The "Commercial" plugs were designed for city delivery vehicles or others where lots of low-speed driving and extended period of engine idling happened. Operational modes which could cause richer mixtures and eventual mis-fires. So more spark energy kept them cleaner as they tended to get gunked-up.

In the late 1960s, some OEMs shortened the length of the rotor tip, sometimes marked with an "E", "for emissions purposes". With the older, longer rotor tip being what was really needed. BUT that wider gap did the same thing as the "Commercial" plugs did, making the coil build more spark energy to better fire the spark plugs. Not unlike gapping the plugs nearer to .040" rhan .035".

In the middle 1990s, the ACDelco RapidFire spark plugs used all of the tricks. A cut-back ground electrode, with 45 degree angles leading up to the center of the ground electrode, for more exposure of the flame kernel to the incoming mixture, plus short splines on the circumference of the center electrode for an attempt at better mixture turbulance in that area. No platinum or such.

NGK V-Gap plugs used a V-cut center electrode with the edges being where the spark jumper, rather than otherwise. Accel had a U-Groove plug that was supposed to accomplish the same thing, but the sharp edges of the NGKs worked better. Even being OEM in Toyotas, which is where I came across them.

I took the Toyota application plug and crossed it into the same heat range/style plus as fit my '80 Newport 360 2bbl. The Autolites in the engine were burning well when I removed them, but as soon as I fired it off with the V-Power plugs, I could tell an immediate difference in throttle response crispness. Maybe even another tenth of mpg increase, too. But it felt nicer to drive, so I put them in everything I had.

By observation, in the combustion chambers which had "lazier air" (as in "open" chambers, as the LA motor had then) vs. "active air" (as a wedge chamber would have), they made more difference. Not to the same extent with the B/RB motors.

One of their alleged benefits (in the Toyota brochure) was that they'd burn leaner mixtures better. In the 305 in my '77 Camaro, I had the electric choke set as lean as it could be and still have good "first mile" driveability. I would touch the accel pedal to set the automatic choke, then hit the key. The car started quickly, but after putting it in gear, if it acted like it was going to die, I could just touch the accel pedal for a bit of pump shot, the engine recovered immediately, and I could back out of the driveway and drive off, to the first stop sign two blocks away. In any weather. By the next two blocks, the choke was off.

But they would only last about 30K miles before the sharp edges of the center electrode would round, so time for a new set. They also had the cut-back ground electrode.

Before using the NGK V-Powers, I had used Motorcraft plugs in our Chevy V-8s. MUCH better durability than ACDelcos by a long shot. I also discovered that a friend had been doing that in his Chevy small blocks for years, too. I went one heat range colder as I had advanced the base timing about 4 degrees, for good measure. NO operational issues and they always colored the ceramic just a hair beige. So, back then, Champions in the Chryslers and Motorcrafts in the Chevies, until I used the Motorcraft and then NGK V-Power plugs in everything.

ONE time, I did bite for the Split Fires. I had very second thoughts at paying close to $50.00 for a set of spark plugs, but so many magazines touted them as better and quicker. After 20K miles, they came out. NO advantages in the Chrysler 360 in the '80 Newport and back to Motorcrafts in it. In that car, they actually ran worse than the Motorcrafts!

In the world of NGK, their heat range numbers run backwards of other brands, higher numbers of colder and vice versa. For any ONE number of spark plug, there can be another number for the same plug, by observation. While the desired plug could be a what the crooss-over and engineering decode chart indicates,there can also be a 4-digit number for the 4-pack of plugs the auto supplies sell by. A bit confusing until you get ALL of the numbers, heat range designation and the "sales pack" numbers. With the V-Power plugs being in their own little world in this area.

Sorry for the length. Just my experiences and observations over 1+M miles of paying attention to spark plugs in our/my cars. Others' experiences might vary.

Take care,
CBODY67
 
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Loadrunner

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I've been fooling around with plugs since old enough to get zapped by a lawnmower coil...

Back in the early days of the Anthropocene era, I cleaned my plugs, never bought new ones.

The engines of the day had severe sludge issues from the oil of the day, and oil return holes in the heads of wideblocks in particular were nearly closed shut by sludge, and as a result in tandem with worn guides, you could get legendary clouds of smoke from the tailpipe on start up, the "mosquito killing option" I called it, when in season.

So I'd make a cleaning/scraping tool from a piece of steel wire, flattened with hammer at the end to provide a thin scraper that goes all the way down the insulator and scrapes it.

NEVER use abrasives cleaning plugs - they could get into your engine - wire brush only, and burnish the plug so carbon won't stick.

These procedure are extremely common on a fouled 2 cycle engine, and "whiskering" takes place on any plug, carbon growing from each side until meeting, shorting plug, as the energy would rather go to ground directly, the old path of least resistance.

Anti foulers could be found for any application in the J.C. Whitney catalog.

I always wondered what these do for your heat range, but I'm sure I ran some.

Which meant the coil had to generate more power to jump the two gaps.

Yep, wider the gap, the bigger the spark, as witnessed by this great tool, you can actually measure your spark output before it peters out.

Screen Shot 2022-10-23 at 10.47.04 AM.png



ONE time, I did bite for the Split Fires.

I also, in a '66 BSA Victor back in the 80's.

It wouldn't start for my ride one night, I was quite furious as I overheated kicking it, stripped off my leathers and threw my helmet.

I went into the garage and found the first plug on the garage floor that had the proper reach that probably came out of a wideblock or slant 6, heat range be damned, screwed it in and the bike fired right up.

Lesson learned about gimmick plugs.

I think they were court ordered not to make wild claims about their plugs for 10 years?
 

Gerald Morris

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The '72 400 2bbl had J-13Ys rather than the prior J-14Ys of the '66 Newport 383 2bbl. Almost all of the old 383 4bbls spec'd J-12Y or J-10Ys. To me, the 10s should be too cold for normal driving, but they had to tolerate long police chase situations, too. So "cold" it was. Even some J-9Ys in the earlier 1960s, IIRC.

From my experiences, "creeping heat" at freeway speeds is not a spark plug heat range issue. But might be an ignition timing issue, sometimes. If the mixture might be causing the heat issue, there should be other performance issues at play, too. But unless the secondaries are open through all of this, their jetting should not be an issue.

NGK Iridiums are re-packaged OEM with GM and Ford. Probably Chrysler too? With their fine-wire electrodes, the ground electrode will not shade the flame kernel as it expands. There are some YouTube videos showing a "big bang" when the spark happens with them, vs normal-configuration spark plugs.

There are a few ways to modify normal spark plugs' ground electrodes, though, to approximate that "big bang", though.

CBODY67

FYI on the '66 4 barrel B/RBs:
1666547920537.png


I agree that this PROBABLY ISN'T the cause of the creeping heat issue. But I thought it would be best to fish for intelligent replies to my query before spending money, having done too much of that already. I might enrich the fuel mixture a little, to see if that changes things. I can even ease the choke in a little for that, just to test the hypothesis before touching so much as a screw. Think I will do that.

The 2 barrel distributor mucks up the idle as soon as I attach vacuum to the advance, but runs it very nicely without. I prefer having vacuum advance working, as this helps the kickdown, which I also need to get back in proper order. I have timing set at the canonical 12.5 degrees BTDC, curb idle 650 rpm for the moment. Oil pressure drops to ~ 9 psi when idling at 600, and w the motor warmed up over 210F. I can and will tweak the pressure relief valve on the pump to bump pressure to a nicer 12 or so psi at warm curb idle. No biggie there. Oil pressure is damned fine running, near 50 psi @ 3500 rpm or more. I'm keeping the revs down a bit for the first 500 mi after this little job. New lifters, rockers, valves to break in. Plenty ZDDP in the crankcase as always.

I hear an occasional squeak from either the water pump or less likely, the alternator. Coolant moves, but it might not be moving just right. If I get any MORE noise from those accessories, I'll diagnose, and replace if needed.

The "TECHNICIAN" we hired knows Chebbeez, not old Mopars, but he was humble enough to realize his limits and to accept guidance from me. I reciprocated. The young fellow (SO MANY OF THOSE NOW! DAMNATION!) has sharp eyes for catching things amiss on his work, such as the tiny crack on that head bolt hole near cylinder #1, and a bit of broken tab laying on the block which came from a distributor shaft. I value such acuity. Still, a modern Chebbee Tech is what he remains, not a seasoned Old Mopar Mechanic. He got his Master's cert, and thus runs his shop. He didn't charge too outrageously either. Still, I doubt I'll use him again. The whole point in us driving these old C body Mopars is to have EASY TO REPAIR AT HOME MOTOR TRANSPORT after all.

Will post more later.
 

Loadrunner

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I can even ease the choke in a little for that

Mechanical choke?

I can and will tweak the pressure relief valve on the pump to bump pressure to a nicer 12 or so psi at warm curb idle.

Watch this, I've done this only to get some smoke from excessive splash via the rods bearings, took the washer back out. Sadly there's no room to pull the pan in a sedan like you can in a Power Wagon, I rebearinged a wideblock in a '65 W200, did wonders for oil pressure and start up noise all gone.

w the motor warmed up over 210F.

These cars were designed around 180º thermostats, 210º seems a tad bit hot and contributes to the low oil pressure warm.

Once it's broke in to your liking, Power Punch or Lucas will increase viscosity index for better idle oil pressure, good coating for startups, clingy.

Had a GF with 300ZX that had run out of oil, filled it up with Power Punch, noisy as hell but it got her to work everyday, the motor had 0 psi at idle warm. Based on her looks I could she could get a very decent trade in on the car in that condition and she did.
 

fury fan

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Read all the experiences above with various sparkplug types. Agreed with most of it, except that I haven't tried any 'fancy' plugs since I was a teen so I have no opinion.

I haven't used Champions in 20 years. Had a few drivability issues, chasing various potential causes, to which my shadetree mechanic/racer buddy told me to get rid of the Champs. After 2 A-B plug changes on 2 cars (removing the Champs) and having the problem disappear, they are now verboten for me. He gave me some crap on car #2 when he saw the Champions in there. (IIRC, Bosch plugs were on his shitlist, too)

For my engines (all bigblocks, all with 100k miles) I use Autolite 86, which is 1 range hotter. Used Autolite in a few smallblocks also, 1 range hotter.
I run MSD-6 ignition boxes and coils, with .050 gaps on the plugs. Perhaps I could see some improvement with some of the cutback electrodes that @CBODY67 mentioned, but I'm content with the improvement from the MSD stuff. (been using MSD on my keeper cars for ~25 years)
 

71FuryGC

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Back in the later 1960s, when I started paying attention to spark plugs, I found a then-new Petersen Publications book on ignition systems at the newsstand. It had lots of Champion references in it. One thing that got my attention, really a few others too, was their "J-Gap" racing plugs. Having the ground electrode only cover 1/2 of the center electrode took less energy to fire and made for a better spark. At a time when it was normal for the ground electrode to completely cover the center electrode.

So one warm Sunday afternoon, I took the plugs out of the then-used-car '66 Newport 383 for a look and re-gap of the OEM Champion J-14Y plugs. I spent hours filing those ground electrodes back to mimic the J-Gap orientation. When done, I could tell that off-idle throttle response was a bit sharper. I smiled. Much later, I used a pair of sharp diagnoal cutters to do the shortening with, then filled things flat, smooth, and sharp with my trusty points file. In more recent times, I tried taking a pair of pliers and gently twisting the ground electrode so it only covered 1/2 of the center electrode. Seemed to work almost as well on my lawnmower engines as the "Quick-Start" lawn mower spark plugs Champion sells.

This was also during the times (middle 1960s) when Champion claimed their spark plugs ran better than other brands, using two Cadillacs with electronic throttle controls at the drag strip. As things later evolved, they were using their "Commercial" plugs rather than their normal OEM plugs. The "Commercial" plugs had an internal air gap the spark had to jump before it got to the spark plug tip. Which meant the coil had to generate more power to jump the two gaps.

The "Commercial" plugs were designed for city delivery vehicles or others where lots of low-speed driving and extended period of engine idling happened. Operational modes which could cause richer mixtures and eventual mis-fires. So more spark energy kept them cleaner as they tended to get gunked-up.

In the late 1960s, some OEMs shortened the length of the rotor tip, sometimes marked with an "E", "for emissions purposes". With the older, longer rotor tip being what was really needed. BUT that wider gap did the same thing as the "Commercial" plugs did, making the coil build more spark energy to better fire the spark plugs. Not unlike gapping the plugs nearer to .040" rhan .035".

In the middle 1990s, the ACDelco RapidFire spark plugs used all of the tricks. A cut-back ground electrode, with 45 degree angles leading up to the center of the ground electrode, for more exposure of the flame kernel to the incoming mixture, plus short splines on the circumference of the center electrode for an attempt at better mixture turbulance in that area. No platinum or such.

NGK V-Gap plugs used a V-cut center electrode with the edges being where the spark jumper, rather than otherwise. Accel had a U-Groove plug that was supposed to accomplish the same thing, but the sharp edges of the NGKs worked better. Even being OEM in Toyotas, which is where I came across them.

I took the Toyota application plug and crossed it into the same heat range/style plus as fit my '80 Newport 360 2bbl. The Autolites in the engine were burning well when I removed them, but as soon as I fired it off with the V-Power plugs, I could tell an immediate difference in throttle response crispness. Maybe even another tenth of mpg increase, too. But it felt nicer to drive, so I put them in everything I had.

By observation, in the combustion chambers which had "lazier air" (as in "open" chambers, as the LA motor had then) vs. "active air" (as a wedge chamber would have), they made more difference. Not to the same extent with the B/RB motors.

One of their alleged benefits (in the Toyota brochure) was that they'd burn leaner mixtures better. In the 305 in my '77 Camaro, I had the electric choke set as lean as it could be and still have good "first mile" driveability. I would touch the accel pedal to set the automatic choke, then hit the key. The car started quickly, but after putting it in gear, if it acted like it was going to die, I could just touch the accel pedal for a bit of pump shot, the engine recovered immediately, and I could back out of the driveway and drive off, to the first stop sign two blocks away. In any weather. By the next two blocks, the choke was off.

But they would only last about 30K miles before the sharp edges of the center electrode would round, so time for a new set. They also had the cut-back ground electrode.

Before using the NGK V-Powers, I had used Motorcraft plugs in our Chevy V-8s. MUCH better durability than ACDelcos by a long shot. I also discovered that a friend had been doing that in his Chevy small blocks for years, too. I went one heat range colder as I had advanced the base timing about 4 degrees, for good measure. NO operational issues and they always colored the ceramic just a hair beige. So, back then, Champions in the Chryslers and Motorcrafts in the Chevies, until I used the Motorcraft and then NGK V-Power plugs in everything.

ONE time, I did bite for the Split Fires. I had very second thoughts at paying close to $50.00 for a set of spark plugs, but so many magazines touted them as better and quicker. After 20K miles, they came out. NO advantages in the Chrysler 360 in the '80 Newport and back to Motorcrafts in it. In that car, they actually ran worse than the Motorcrafts!

In the world of NGK, their heat range numbers run backwards of other brands, higher numbers of colder and vice versa. For any ONE number of spark plug, there can be another number for the same plug, by observation. While the desired plug could be a what the crooss-over and engineering decode chart indicates,there can also be a 4-digit number for the 4-pack of plugs the auto supplies sell by. A bit confusing until you get ALL of the numbers, heat range designation and the "sales pack" numbers. With the V-Power plugs being in their own little world in this area.

Sorry for the length. Just my experiences and observations over 1+M miles of paying attention to spark plugs in our/my cars. Others' experiences might vary.

Take care,
CBODY67
I've been thinking about replacing the plugs in my 71 360 with a set of NGK 2635 V Power as they call it (recomended as compatible on Napaonline and NGK.com). Currently I have a set of Champion RN14YC which seem to be doing ok. I don't think I'd find another set of those if I tried and have no idea how long they have been in the car. I run 91 octane without ethanol and have the timing retarded about 5 1/2 degrees from original specs. Otherwise largely an "as Built" drivetrain. Any opinions appreciated.
Thanks in advance.

IMG_20221104_100557.jpg
 

ayilar

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I've been thinking about replacing the plugs in my 71 360 (…) Currently I have a set of Champion RN14YC which seem to be doing ok. I don't think I'd find another set of those if I tried

Try Summit. Those are the RJ14YC that I have been using on my cars.
 

fury fan

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Yes, R is resistor.
14 is the heat range, 16 is 1 step hotter.
IIRC the J vs N specifies the reach (the length of threads).
I'm betting that J is bigblock and N goes to smallblock.
 

CBODY67

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"J" and "N" relate to the number of threads on the plug. "J" is shorter and "N" is longer.
 

CBODY67

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There should be a "decode list" of each segment for NGK's, Autolites, and Champion spark plugs online somewhere. Only thing is that for the NGK, you'll need the "long number" (alphanumeric, similar to the Champion part number) rather than the "sales number" (4-digits). The "long number" is the one stamped into the spark plug, too. The "sales number" is the number stamped on the box the 4 spark plugs are sold in.

The "segments" would include: thread reach, heat range number, gap style, extended center electrodes, design spark gap spec, resistor, and copper core (where applicable).

In the NGKs, the heat range number increases as it gets colder, the opposite of other spark plugs, where the number increases as it gets hotter.

The other thing is that NGK heat ranges seem to be wider than other brands' heat ranges. Just an observation.

The thread reach has nothing to do with "big block" or "small block" per se, as some aluminum B/RB heads can use the "N" spark plugs, IF that's what the heads were designed to use. Just as small block Chevy V-8s can use a "J" Champion plug, too. But in the case of Chrysler-specific engines, the Js are B/RB and Ns are LA.

CBODY67
 

ayilar

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IIRC the J vs N specifies the reach (the length of threads).
I'm betting that J is bigblock and N goes to smallblock.
in the case of Chrysler-specific engines, the Js are B/RB and Ns are LA.
Thank you both. All but one of my engines are big blocks, and I have installed the RJ14YC on BBs only.
 

CBODY67

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Update . . .

Rather than chase online decode lists, you can download the NGK master catalog (all 400+ pages of it) in a PDF file from the NGK website. Has compeetitor equivalances in the back sections. But the oldest listing is for 1985 in the model listings. Plus which "sales/stock number" goes with which "long number", too. AND the master decode listings spread across two pages near the front. Downloads quite quickly, too.

Might find similar catalogs for Champion spark plugs and Autolites, too.

FYI,
CBODY67
 
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