Hot Rods was any of it true?

About 20 years ago there was excitement over new technology for spark plugs. Plugs that would offer four sparks at once! All kinds of different plugs for all kinds of performance vehicles. It seems to me all these plugs are now gone and we have returned to the basic original design of a spark plug. My question is was the hype of 20 years ago simply hype, or did add up to any sort of performance gain?

 

The genius of marketing....that's all.

 

No



Bones

 

Got me. I tried using a variety of different plugs in my early hemi's I ended up using a split fire plug with a GM HEI and a hotter coil, I also tried a couple of different brands of wires, different counter weights, different springs, the split fire plugs worked best, burned the cleanest with Pemex, was there any performance improvement? hell if I know.

 

Not 4 sparks at once, just a longer service life, over a conventional plug.

 

I always thought electricity took the path of least resistance.

 

If you think the spark came from all four of those electrodes at once.... I got a bridge I want to sell, give me a call.



Bones

 

Was that before or after cow magnets?

 

I use those to keep my cows from wandering off. It's like an invisible fence.

 

Hope those Splitfire guys don't choke on their caviar when they see this.

 

i've never used them Bosch plugs myself , but at the auto parts store where i work part time we had a lot of them returned from unhappy customers

i can see a benefit from more spark or more spark plugs per cylinder. on a typical small aircraft engine with dual magnetos and dual spark plugs you will lose about 50 RPMs when switching from both mags to left only or right mag only while doing the engine run up before take off. if you lose about 100 or more you need to get things checked out

FYI....the Dodge 5.7 Hemi has two plugs per cylinder

 

I sent an email to the manufacturer of the 4 electrode plug and asked him how to set the gap.
his answer: you never have to.....

 

Even with those plugs there's still only one electrode, just now there's 4 path's to ground.

 

I used to have an old AC spark plug cleaner and tester, sand blasted and cleaned the plugs. You tested them with a built in coil and air pressure that was adjustable. We tested multiple brands of plugs the split fires were the worst of the lot! Best performer of all was Bosch Platinum.You could actually see the plug firing through a small glass window when testing.wish I still had that old machine it worked well wired to the edge of my parts counter to repel people who bothered me!

 

That is what MSD does.

 

I had an OT import from the mid 70's almost 40 years ago that used NGK plugs with three electrodes and it also had dual points. Nothing new.

 

The only purpose of many of the performance and mileage gimmicks of the past and today is to separate people from their money.

 

My all time favorite was engine rebuild in a can, followed by that little fan you placed under the carburetor and what was that calcium carbonate (limestone) oil adative?

 

I always wondered about the spring loaded cam sprocket. You don’t see them anymore.

 

When I was in high school and in high school auto shop there was an old fart in town that seemed to buy every "gas mileage improving" trinket that came about and stick them on his car and when the car wouldn't run very well he brought it to the school shop for us to straighten out. We pulled the trinkets off and put them in a special box in a store room that was just for trinkets off his car. When the teacher took a job at a trade school he presented the box full of trinkets to the gent.

 

Always wondered why autos didn't use "surface-gap" or "perma-gap" plugs like Mercury marine used?
I guess differences in 2 vs 4 stroke combustion chamber and ignition requirements?

 

https://4.bp.blogspot.com/-1nhsMDVP...JgUMnCJCcORZwwChiMACLcB/s640/4+underlined.bmp

 

I believe those 4-prong Spark Plugs were developed for Aircraft Engines either prior to, or during, WWII, so if a plug wore out one gap there would be another one available so the engine wouldn't lose power(sort of important when you can't just pull over & re-gap your plugs)

 

I will say this, I use to have a Honda 600 single cyl enduro bike. Kick start. I rode it to work most days and on cold mornings it was a bear to kick start. Tried several different plugs and when I put in an NGK 'Hot U' plug it would kick to life every time. That sold me on NGK plugs. I dont think the make the 'U' electrode anymore, now the have a V shape... same principle. I run them or the Iridium in pretty much everything

 

The sparks slowly erodes away metal from the electrodes. Multi-electrode spark plugs has more metal available, meaning they can last longer. The downside of all that metal is that you need a bit more energy from the ignition system to create a spark, so with a borderline too weak ignition system you may have problems at high rpm.

 

Yes it was hype the suckers didn't give the performance they promised, so to make yourself feel better about spending all the extra amount of money you made your mind up that they were better so you didn't feel so stupid for buying them.

 

Wonder if those extra ground electrodes actually get used or just get a layer of carbon and foul out.

I have some platinum plugs with over 100k and still going.

 

I have a coffee can full of surface gap spark plugs that I bought at a swap meet years ago. The coffee can had "REATH" written on it, and the plugs are early hemi head length. Used Joe Reath hardware?

Can you explain why you need more energy from the ignition system on a multi-electrode plug? Your comment doesn't make any sense to me.

The fouling that occurs on any spark plug is due to one of two possibilities. One is the buildup of compounds (carbon, oil, wet gasoline)on the ceramic insulator of the spark plug. Enough buildup and those compounds provide a path of less resistance than that of the gap between the center and ground electrode of the plug. Kapow, all the energy that would normally provide a spark slithers through those compounds to ground.

The other form of fouling is a buildup of compounds that bridge the gap between the center and ground electrodes. Usually this is because of too cold a plug and excessive oil burning.

If f you have a good plug with no fouling of the ceramic you could coat the ground electrodes with peanut butter and dog shit and they would still work.

 

Compare the spark plug to a capacitor.
The capacitor is made from two layers of metal, sometimes rather small on opposite sides of a ceramic disc, larger ones may be two layers of metal foil rolled together, with paper, plastic or some other insulation in between. When you apply a voltage to these two layers it takes a charge, basically like a battery - current goes in, voltage goes up, and when it is charged it can be discharged through, say, a light bulb for a brief moment. Bigger surface area of the foil means a bigger capacity capacitor.

Now, if you look at the spark plug... Two electrodes, separated by air. It's a piss poor design for a capacitor, but it does have the building blocks and it does require some current to get charged up to a high enough voltage for the spark to jump the gap. More & bigger electrodes means more current is needed to get the voltage to raise as high, no problem if you have a beefy ignition system but if you run a stock points ignition an a high rpm engine with many cylinders there might not be enough energy output from the ignition coil to get a high enough voltage to produce a spark. You probably won't notice it unless you run the engine on a very sensitive dyno and compare different ignition setups, but say it misses one spark out of 100, that's 1% power lost.

For the same reason (and others) you want to keep your ignition wires clear from other metal parts. Letting them lie straight on the valve covers may cause problems you wouldn't have if they were held up with something insulating. When they get old and the wires insulation degrades, keeping the wires away from metal also reduces the risk of the spark punching through the insulation and going straight to grounded metal.

About spark plug electrodes, sparks also needs a different voltage depending on the shape of the electrodes it jumps between. Narrow electrodes with sharp edges need a low voltage, more rounded edges (as old plugs get from wear) need a higher voltage. This is why some spark plugs incorporate a groove in the middle of the electrode, more sharp edges for the spark to jump off, takes more time to wear them round.