Diamond Spark Plugs?

I keep hearing (mostly from the young folks) about how wonderful diamond plugs are. Are they that good? Do they have to be Gapped or adjusted? Should I changed to these plugs on my XJ-6?
Chris

according to their website, they could be worth 3-6% increase in power. Don’t know how noticeable that would be. Can’t hurt to try them out.

They have non-adjustable gaps.

Stay with the OEM recommendations too many YT videos that have negative reviews to even try them.

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Don’t bother, Chris, use OEM - Champions, tested through years…

I’d like to know how one measures 3 - 6% increase in power - and how that can be ascribed to spark plugs…:slight_smile:

Frank
xj6 85 Sov Europe (UK/NZ)
**.

My litmus test for so-called “innovations” in automotive technology - do OEM’s use them? If they do, they might be useful. If not, they’re most likely worthless.

If OEM’s use these “Diamond” plugs, then maybe they might have some value. Though if they did work, I don’t know why an OEM would spend $50+ million revising a engine to get a few percent better power when they could just stick these plugs in and get 6% with no engineering effort required.

Dave

To get the full benefit from these plugs, be sure to attach a magnet to your fuel filter , which will energize the fuel molecules, giving even more power.
Dave.

2 Likes

Only if it’s a billet magnet.

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And of course an inlet turbulator, Dave…! :slight_smile:

Frank
xj6 85 Sov Europe (UK/NZ)
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Ditto:

  1. Do I surmise that they cost more than Champions, and the like??

  2. Yeah, swap[ping out a worn and dirty set of any specie for a new set will result in a better running engine.

  3. At the end of last year, my daughter’s experienced Passat had miss issues, some an outright stall!!!

A neighbor put his scanner on it and it read misses at times on as many as 5 of it’s 6 cylinders!!!

To me, I interpreted as ignition rather than fueling!!

I got a new coil pack, HT leads and spark plugs.

I removed the existing plugs and found multi gap “fawncy” NGK’s!!! They looked OK???

The new plugs were conventional electrode NGK’s.

It fired immediately and ran sweet. But, daughter had lost faith and swapped it in for a much newer Nissan.

Carl

YEARS ago, when muli-ground electrode plugs made yet ANOTHER comeback (they showed up in the 20s), I tried them in my dyno test engine.

They provided NO MEASUREABLE effect on any parameter, except lightening the car.

By the removal of money from your wallet.

Ergo the missing 3-6% ‘power gain’. :slight_smile:

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I use these plugs pretty much exclusively. If you have an oil burner. Then definitely. These are considered non flowler plugs. I like the E3 plugs because there is more surface to for spark.
Other than that, I use champion plugs. On pre- engine managed Jags, I stick to copper core plugs. I’ve found the stock ignition doesn’t produce enough juice to take advantage of the platinum or Iridium core plugs.

With the diamond spark plugs, I have found I get a good blue spark, and a consistent burn pattern across all of the plugs.

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They work OK, Mark - it’s the claims of increased power that is doubtful…:slight_smile:

The sole job of the spark plug is to ignite the mixture. The flame front then spreads out from the ignition point at about 40 m/s (some130 ft/s) - the ign source is immaterial. Engine power is related to ignition timing - which is adjustable.

Also, with ‘multipoint’ spark plug electrodes; the spark occurs on the point with the least resistance - the others are redundant/‘spares’…

Frank
xj6 85 Sov Europe (UK/NZ)
**

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Let’s not forget the in-line magnetic “fuel electron aligner.”

:roll_eyes:

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I vaguely recall that the magnet that improved fuel molecular alignment was derived from the dairy industry,. In some manner helped cows to provide more milk??? GMA milk???

On the order of the carb to manifold inserts with a fine screen to improver vaporization.

Carl
Carl

More Power? Ummm no. That hasn’t been my experience.

Exactly. My first run in with multi point plugs was with my '72 Chevy Vega. My sister drove it for a couple of weeks, overheated the engine, and It burned oil like no other ever since (well not really, I pulled the engine and had it sleeved). I ran straight 50 weight oil. I couldn’t keep plugs in it for more than a week or two. I was working in an auto parts store at the time, and the owner said try these plugs. It was my introduction into multi-point plug, wasn’t an E3 plug. I can’t remember what they were called I just remember the box was red and blue. The plug look something like this.
image

Anyway, I could get a couple of months with these plugs before they’d fowl. That my was the second car my sister killed. Thanx Dad!

What I do know, is these plugs are a bitch to gap.

Here’s one for you. I did a bit of Internet poking. and found this Multi-point plug.


Snake Oil or the real thing?

Here’s the catalog

Anyone?

I’m curious. I’d give them a try to see if there is anything to their claim. Rather expensive though.

Pure snake oil. Nothing else.

Mark:

I’ll bet. I would not have had the foggiest as to how at that time, or even now. My guess is 'not needed".

At one time we had a neat little 71 AMC Hornet coupe. Actually a Rambler. Nice 232 6. FMX transmission. Very spunky, could and di best a couple of SBC’s off the line…

It came to us used, in 73, low mileage and clean. At first t fouled plugs at times. til I replaced them .all with some of a hotter range.

And, t liked to eat starter pinions. At first bargain priced ones. And, then I got a “good” name brand unit. Solved.

Carl