Type of Champion Plug for 1968 383 ?

Ghostultramarine

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I have a '68 Newport with a 383 2 barrel and was wondering which type of Champion spark plug I should be looking at.

The RJ14YC vs the J14Y?

The 'R', I know, means "resistance", but I'm not exactly sure how what might affect things.

Any advice would be welcome.
 
The FSM states J14Y for the 2 bbl 383.

I’ve got a line on a guy who has both RJ14YC and J14Y plugs.

Which should I get and why?

He wants a bit more for the J14y than the resistance plugs.
 
The FSM states J14Y for the 2 bbl 383.

I’ve got a line on a guy who has both RJ14YC and J14Y plugs.

Which should I get and why?

He wants a bit more for the J14y than the resistance plugs.

If you are running modern soft core resistance plug wires, you do not need a resistor plug, but running a resistor plug with resistance wires usually won't hurt anything. Back in the day, cars with radios usually specified resistance plugs to keep the static down on hard wire core plug wires. The "C" at the end of the modern plug number signifies copper for better conductivity of the plug electrode. Modern plugs have a somewhat wider heat range for adaptability to many applications. J14Y plugs have been out of production for a long time and they are the correct vintage plug number, not a big deal unless this is a high points restoration. That is why they command a premium price.

Dave
 
Thank you.

It’s not a high points restoration. I want plugs that will run good and perform well.

I just wanted to know if the R would affect anything.

I’m going to guess they’re soft-core as they’re modern wires.
 
RJ14YC is what is listed for the 2 barrel 383. That's what I would run. I got spanked with Autolite's crossover on my small block. One heat range too cold and it wouldn't idle clean. Screwed in the correct Champions and problem solved.
 
Never used 'AutoLite" plugs, just the later Motorcraft equivalents. Never had any issues with the OEM J-14Y Champions in our '66 Newport 383 2bbl. Got a few re-gaps out of them before they were replaced. I discovered that the Motorcraft equivalents would actually last longer than the Champions. I later suspected that so many posters had changed to Autolite as they were available at a good price, which is fine by me.

Even with good resistance wires, with the hood open and the engine running, you can hear some static in the AM radio, but it mostly goes away when the hood is closed. Adding the resistance might help that, especially with an FM radio.

As long as the engine is not burning a lot of oil, the J-12Y to J-14Y plugs should work pretty well. No real need to chase the expensive NOS plugs when other brands are somewhat readily available. A main thing would be the normal-type plugs or the more expensive Iridium plugs, depending upon how many miles you might drive between plug changes. OR how much time you might need to spend "in the garage" changing them every so often.

Enjoy!
CBODY67
 
That’s why you go get some autolite 85’s and lif is good.

I tried to give him the info on how to read champion plug numbers, but he didn’t read it.
 
In following ANY plug cross-over, I discovered that you should first decode the spark plug you currently have/OEM specs. Then do the same for the potential-use plug to see if it matches in all respects, for best results.

Many plug makers/sellers have a reasonably easy decode, but NGKs can be a bit daunting by comparison. Other than the fact that their heat range numbers go backwards to other manufacturers heat range sequences.

And THEN you can get into the issues of whether to open the factory-spec gaps a bit . . .

Enjoy!
CBODY67
 
That’s why you go get some autolite 85’s and lif is good.

I tried to give him the info on how to read champion plug numbers, but he didn’t read it.

I looked at it. I did not know for sure if the 4 extra mm would make them unusable.

The chart also has absolutely no explanation of the advantages and disadvantages of each individual designation.

But hey, it’s always good to assume.
 
In following ANY plug cross-over, I discovered that you should first decode the spark plug you currently have/OEM specs. Then do the same for the potential-use plug to see if it matches in all respects, for best results.

Many plug makers/sellers have a reasonably easy decode, but NGKs can be a bit daunting by comparison. Other than the fact that their heat range numbers go backwards to other manufacturers heat range sequences.

And THEN you can get into the issues of whether to open the factory-spec gaps a bit . . .

Enjoy!
CBODY67

Yes, it is a bit daunting. Especially when you find out most of the people working in auto parts stores don’t seem to know much beyond reading a computer screen and even online articles can contradict each other and forums can be worse.
 
I looked at it. I did not know for sure if the 4 extra mm would make them unusable.

The chart also has absolutely no explanation of the advantages and disadvantages of each individual designation.

But hey, it’s always good to assume.

Do you buy your bolts with an extra 4mm and think they will fit the hole? That won’t work will it? 4mm = 0.157. 0.15625 is 5/32 Now do you think it will work?

The chart is a factual reference to decode the numbers. It has no feeling or emotion, it won’t help you to decide what to buy based on these human emotions. Seek guidance elsewhere.

assume is what you did. How did it work out?
 
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I sure wouldn't rely on a conversion chart for the correct off brand plug. They can be off a heat range or two which can cause issues. My 383's came with Champions and that's what I like using.
 
I sure wouldn't rely on a conversion chart for the correct off brand plug. They can be off a heat range or two which can cause issues. My 383's came with Champions and that's what I like using.

Did you even look at it?
 
I sure wouldn't rely on a conversion chart for the correct off brand plug. Thecan be off a heat range or two which can cause issues. My 383's came with Champions and that's what I like using.

There's an old "default mode" orientation. . . to use what came in it from the factory, UNLESS you have found something that might work better . . . including last longer and possibly also cost less or be easier to get. FWIW

Enjoy!
CBODY67
 
FWIW 4 me, I run the NOS Champion plugs when I can get them for $2 ea or less. Folks might be surprised to find this isn't that difficult, with a well tuned search algorithm to help. Granted, plenty folks sell NOS stuff for absurdly high prices. I'm too poor for that.

I'm definitely sticking with Champion JY*13-14 plugs. The FSM recommends them, and I have no pre-ignition with them, unlike the JY*11-12 plugs I've experimented with. I've used both Autolite 85s of several sorts, and Bosch plugs, and while they did decently, I got the best results with the Champions thus far. I remain open to some experimentation, as time, budget and other circumstances come into play, but knowing I have such a good base line performance with the old Champions comforts me mightily.
 
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