Who sells NGK BCP6ES?

Who sells NGK 4930 (BCP6ES)? Summit says they have been discontinued.

Try Google

I did and a lot of websites says discontinued.

Yep, almost all or everyone that I searched (Amazon, ebay, motorcycle, ATV parts distributors, etc.,) say NOT AVAILABLE??

i just bought 8 yesterday from Advanced Auto.They were in stock.

Napaonline.com shows them available

Ebay shows lots of listings

Thanks. Going to Napa today to see if they have them.

Try BCPR6ES.

Same specs but has a resistor.

I got the last 16 from Napa.

What is the difference between a resistor and non resistor?

https://www.ngk.com/what-is-a-resistor-spark-plug

unless the application is an all out race effort, resistor plugs will work fine.
just choose the heat range that will work the best for a particular combination.

On my race bikes I try to avoid a resistor spark plug. Cars and motorcycles have been coming with a 5k ohm resistor spark plug caps for a long time and I see no reason to add in more spark energy resistance. Maybe if my AM radio starts to have RFI then and only then would I run an additional resistor in the form of a resistor spark plug. Just me.

https://www.ebay.com/sch/i.html?_fr...570.l1313&_nkw=NGK+4930&_sacat=0

Superceded to a 2330 stock number. Same plug.

No. 2330 is the Resistor plug.

WHAT IS A RESISTOR SPARK PLUG?
Spark Plug Resistor Location

At the moment the spark jumps the gap it causes a high frequency burst of energy, known as RFI (radio frequency interference). RFI, as its name suggests, creates static on your radio and interference with other electronic equipment, including the vehicle’s on-board electronic control units (ECUs).

Resistor plugs were developed in the 1960s to suppress some of the spark energy, thus lowering RFI to an acceptable level. Most resistor spark plugs use a monolithic resistor, generally made of graphite and glass materials, to filter the electrical voltage as it passes through the center electrode.

Since resistor type plugs actually “resist” some of the spark energy, non-resistor type plugs actually deliver a more powerful spark. It is for this reason that most racing plugs are non-resistor types. However, in most automotive applications, a resistor plug is required for proper vehicle operation. Use of non-resistor plugs in vehicles that call for a resistor type can result in rough idling, high-rpm misfire, and abnormal combustion.

You can buy direct from NGKs website if they have them:

https://www.ngk.com/ngk-4930-bcp6es-nickel-spark-plug

Says Discontinued, and to use NGK 2330

https://www.ngk.com/ngk-2330-bcpr6es-nickel-spark-plug

As you increase the ohmic resistance of the sparking system,
either by adding a resistor to the spark plug
or adding resistance to the wire,
the “burn time” of the spark increases.

Having a very intense spark with high current but for very short time,
by experiment has been found to result in more “misfires.”

Lowest misfire rate happens at the compromise where the spark intensity is “good enough” and when the time the spark endures is relatively long,
by experiment has been found to result in lowest possible misfires rate,

At high rpm a single coil does not have time to “recover” before the next cylinder fires.
Misfire rate at high rpm can be reduced at by having a coil for each cylinder.

Misfire rate can be further reduced by having two (or more) spark plugs per cylinder, each with its own coil.
( 5.7 Hemi set up)

Seems excessively crazy,
but an MIT student wrote his Master’s thesis about finding how many spark plugs per cylinder were needed to reduce the misfire rate to zero.
He got up to 16 spark plugs on a single cylinder and was still finding improvement.
The single cylinder, variable compression ratio, side valve design, CFR engine he was using has a combustion chamber design that lacks modern “overhead valve” engine design with quench, swirl, or tumble.

Your MIT example negates your increased resistance claim.

As you add resistance in parallel ( more plugs in this case) over all resistance drops.

You need to cite both claims to make a coherent conclusion.

And bet he never built a race engine and did dyno testing to prove or disprove his findings

If this is a street car then take a look at NGK 6987. It has a projected tip and an extra wide spark gap. I use the 6987 on all of my street engines, even use them on pump gas race engines. Best plug for the price that I've found.

Thank you. It is a street car with Edelbrock heads and 500hp.

The NGK 6987 is a factory plug in some Mopars. Used in the V10 and 4.7 engines as well as a few others.

The Master’s student did have a dyno measuring the output of his little CFR engine with one cylinder and whose side valve head design is about as far from “modern race engine” as one can imagine.

The idea that he was also so clueless that he hooked up 16 spark plugs to a single ignition coil so as to create 16 parallel electrical circuits with lower ohms of circuit resistance says more about Sniper’s view of reality than even I previously suspected.

There were 16 separate ignition systems to insure each spark was equivalent.
But the sparks were not anywhere near “optimum” combustion chamber locations, especially spark locations 5 through 16.
Imagine drilling and tapping 16 holes without having a crack run from one close hole to another.

Give the little CFR engine with its variable compression ratio its due respect though.
It was used to discover Octane, Triptane, Tetra-Ethyl Lead and other “Octane Rating Improvement Additives”
At one time these were valuable “Military Advantages.”
MIT PhD student Col Jimmy Dolittle used 130 Octane Rating Triptane aviation fuel during his bomber raid on Tokyo.

Did this student go onto a job with Chrysler/Ford/General Motors/Other where he designed, built, and dyno tested engines?
I do not know but I would not be surprised if he did.

https://www.oreillyauto.com/detail/...ug-number-zfr6f-11g-spark-plug/ngk6/6987

Good looking plug.

I have wondered in the past whether the V10 plug was better for a towing duty 5.9 V8
I have wondered in the past whether cylinders 7 and 8 on a 5.9 V8 need a different spec or design plug.

If you have a projected nose,
should you worry at all about the longer ground strap getting too hot at high load?

https://www.enginelabs.com/engine-t...lug-debate-separating-fact-from-opinion/

Along with longer ground strap changes, what about multiple ground strap changes? Autolite view:

https://www.autolite.com/docs/defau...s/understanding-mge-spark-plugs-2017.pdf

I confess to spending way to much time
indexing spark plugs,
cutting off with a Dremel tool the particular ground straps of Bosch +4 that ended up nearest the exhaust valve off, making them into custom Bosch+3.

I now like NGK Iridium projected nose plugs where great factory quality control and longer life justifies higher cost.

I like the no longer sold
KAL Equip 2969 spark plug analyzer
with its Peak KV, Burn KV and burn time readings,
although it does not work well with “wasted spark” type ignition systems.
I eventually bought another used KAL Equip 2969 unit for $70
to have two so as to more easily compare “known good” cylinder to “suspect” cylinder at the same instant in time.

If you “on purpose” create an air leak at a cylinder for lean a/f
or add propane to a cylinder to create richer a/f
the KAL 2969 is sensitive enough with its 3 readouts to show a/f differences.

The cluelessness is your assumption he used 16 separate ignition systems. You claim chit without sourcing and try to come off as oh so superior when called on it, lol.

Care to talk about wasted spark systems? that have parallel paths to ground and what that does to resistance?