NGK spark plugs breaking.

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Thanks, Dan. I know you recommend going with the NGK ZFR5N plugs for my stock 1974 slant, but if you did go to a Champion plug, which one would you use? I don't think Champion makes the N14Y any more. Thanks!

RC14YC is the same plug as the N14. The only difference is the N plug had a 13/16 hex and the C plug has a 5/8 hex. The 5/8 hex is much nicer.

Edit: I’ve seen as many NGK and Autolites with bent ground wires, off set insulators and everything else.

I’ve used and still do use Champions in virtually everything I tune. They are easier to read.

So this bullshit that NGK’s are a step up from anything is nonsense.

I’ve pulled and replaced more NGK and Autolite plugs and made more power so many times I can’t count.
 
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I saw that thread and I gotta say I've never had trouble using a regular socket for spark plugs. Although there are some instances where the rubber does help hold the plug in. As long as you support the head of the ratchet when you tighten them, you'll never break one. It's when you pull it tight and don't support it that the trouble comes in, because you tend to pull at an angle. When you do that, you'll crack the insulator almost every time. I've used the fuel hose trick a lot though.
 
RC14YC is the same plug as the N14. The only difference is the N plug had a 13/16 hex and the C plug has a 5/8 hex. The 5/8 hex is much nicer.

Edit: I’ve seen as many NGK and Autolites with bent ground wires, off set insulators and everything else.

I’ve used and still do use Champions in virtually everything I tune. They are easier to read.

So this bullshit that NGK’s are a step up from anything is nonsense.

I’ve pulled and replaced more NGK and Autolite plugs and made more power so many times I can’t count.
Everyone has manufacturing issues at one time or another. It is how the problems are handled. Several years ago I had problems with champions not lasting in my race car. Within a couple of weeks I would get a misfire, which I couldn't diagnose. I wound up doing back to back testing at the track. Isolated the problem to the plugs (used autolites ran fine, Champs misfired). I sent the plugs back to Champion explaining the problem. Champion just responded with "there is nothing wrong with the plugs". Didn't even bother to send them back, offer another set, nothing. I also had a problem with a boxed wrong Autolite. Just one plug out of eight. Heat range was 5 steps hotter than what the box said. Found it after I had a misfire, and pulled the plug. I sent it to Autolite, along with the box(es). They sent me a message apologizing, offered to pay for any engine damage (there was none), and sent me a case of plugs "for my inconvenience".
 
I hate to agree but the Champion plugs have been slipping for a time now. They were my favorite plug at one time. Now I use either Autolite or NGK.
Autolite used to be on my ok-list, many years ago. That stopped when they started being made in China and quality dropped noticeably.
 
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Why are you removing the sealing washer? I'm thinking that is bringing your plugs a bit closer to the piston, causing the breakage.
 
Why are you removing the sealing washer? I'm thinking that is bringing your plugs a bit closer to the piston, causing the breakage.
The spark plug tube acts as the washer. If you leave the factory washers in place, now you have two washers and that creates a faulty seal with the cylinder.
 
Nope. The thread length of the ZFR5N is identical to that of a Champion N14Y (original plug on pre-'75 Slant-6s and on approximately seventy-three million LA V8s). The electrodes are longer, which is the point of using these plugs—they move the spark away from metal-wall quenchout zones, for more consistent ignition of even marginal mixtures. Of course, they aren't a universal drop-in for any/every engine, because yeah, you do have to make sure the pistons won't smack the electrodes. There's adequate clearance on stock and near-stock 225s and 318s and 2.2/2.5 nonturbos and a fair good whack of other Mopar motors.



There aren't any spark plugs listed for /6 Jeeps because there aren't any /6 Jeeps, number one. Number two, constraining yourself to what you think you see in the listings sometimes means you aren't going to get where you want to be.
What you be talkin', no 6 Jeeps? Lots were built with the 258 AMC 6.
 
Just like every other "magic" spark plug gimmick in the history of ever, they don't do what's claimed. Yet another scam from China.


I'm no expert, but doesn't electricity travel the path of least resistance? The plugs designed with numerous ground electrodes still will only fire on one of those electrodes at a time. The way I see it, the E3 design would actually shroud the spark, depending on how the plug is situated in the cylinder. I don't believe it will throw multiple sparks during a single spark event. I would think that indexing your plugs would work as well if not better than those other designs. Please correct me if I'm wrong.
 
RC14YC is the same plug as the N14. The only difference is the N plug had a 13/16 hex and the C plug has a 5/8 hex. The 5/8 hex is much nicer.

Edit: I’ve seen as many NGK and Autolites with bent ground wires, off set insulators and everything else.

I’ve used and still do use Champions in virtually everything I tune. They are easier to read.

So this bullshit that NGK’s are a step up from anything is nonsense.

I’ve pulled and replaced more NGK and Autolite plugs and made more power so many times I can’t count.
I would respectfully disagree. My first Mopar was a 1971 Charger, that I had transplanted a 340 into. I kept getting a misfire, and would change the plugs out, using the same factory recommended Champion plugs. The misfire always found it's way back. So, having a friend who was a mechanic, I went to him for advice. The first question he asked was if I was using Champion plugs. When I answered to the affirmative, he suggested that I changed to Autolite plugs. Never had another misfire after that.
Maybe it's just my luck, but I've never had good luck with Champion plugs, no matter what the application was. Just sayin'.
 
I would respectfully disagree. My first Mopar was a 1971 Charger, that I had transplanted a 340 into. I kept getting a misfire, and would change the plugs out, using the same factory recommended Champion plugs. The misfire always found it's way back. So, having a friend who was a mechanic, I went to him for advice. The first question he asked was if I was using Champion plugs. When I answered to the affirmative, he suggested that I changed to Autolite plugs. Never had another misfire after that.
Maybe it's just my luck, but I've never had good luck with Champion plugs, no matter what the application was. Just sayin'.


And yet, I haven’t had a failure in all these years.
 
Hey, just putting in my $.02. It happened.


I’m sure it did.

I’ve always wondered about distribution patterns across the country.

It seems almost like some regions started getting Chinese or Mexican made plugs sooner than the rest of us.

It seems strange the discrepancies we see. And it’s not just plugs.
 
Champion copper core plugs in my Mopars. I've personally not had a plug outperform them at the strip. I've tried accel, splitfire, sonic power, autolite, NGK etc. etc. I generally don't change my plugs once they are in either. Never have to.
 
I’m sure it did.

I’ve always wondered about distribution patterns across the country.

It seems almost like some regions started getting Chinese or Mexican made plugs sooner than the rest of us.

It seems strange the discrepancies we see. And it’s not just plugs.
A little birdie tole Me that instead of pitching QC 2nd's & 3rd's in the dumpster & writing them off, Chumpion was given to packaging them & selling them dirt-cheap to discount stores, like Kmart, G.C.Murphy, etc., & I just might happen to know 1st hand a fresh tune-up on an AAR sporting a MP PS 292° that barely ran or idled & after exhausting a few other wild guesses...... ran like a pup after re-installing the old plugs at My suggestion. This would've been around '92-'93ish...
 
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