Rounding off the sides of the spark plug ground strap

[bigjoe1]

I was referring to my winning Engine Master SB Chevy-- It was 364 inches--615 HP-- I put the trick ultra thin platinum plugs in for the contingency money, and it LOST five HP, but I ran them anyhow, just for the money ( 5000 dollars )


JOE SHERMAN RACING

[user-17438]

Anybody ever test the Autolite "X" plugs that NASCAR used at one time?

Yes. Used a lot of them. Ar3933X and AR3910x dont have to worry about grounding straps falling off, lol.

[Rizzle]

I see several Engine Masters Competitors using distributors on engines that were originally COP??
Must be some reason ...

Thanks
Randy

Its what they know. Thats it.

How about that EMC hemi, it certainly didn't come with COP, or EFI.

[pamotorman]

"Gapless" racing spark plug. I think it's NGK.

this type of plug was used in 2 stroke snowmobile engines back in the early 60s when electronic ignition boxes first came out

[Sweet P]

David Vizard references rounding off the corners of the ground strap in one of his books, for what it worth.

http://www.ngksparkplugs.com/docs/racing_catalog.pdf

A common blown alky spark plug (IE preignition/detonation prone) is NGK R6061 and these have firing end "G" from page 2, notice that it is like what "BOOT" was talking about in his post.

Supposedly the heat range of the plug only changes the temperature of the electrode, not the ground strap. So the ground strap of a NGK -8 is just as cold as a NGK -11.

[Olefud]

There are so many fallacies concerning spark, what is worthwhile ? Cutting back grounding straps, multiple sparks, higher energy, etc..
If adequate is enough, what helps more besides accuracy ?

You may be right. But when I was long ago racing 2-cycle performance would slowly fall off only to be revived with a new plug. So it’s probably not binary, i.e. works just fine till it quits.

[englertracing]

I was referring to my winning Engine Master SB Chevy-- It was 364 inches--615 HP-- I put the trick ultra thin platinum plugs in for the contingency money, and it LOST five HP, but I ran them anyhow, just for the money ( 5000 dollars )


JOE SHERMAN RACING

its surprising that you lost power.... Hmm.

[MadBill]

I've heard it more than once before. The GM guy in charge of the nuts and bolts of the showroom stock Corvette race series in the late eighties told me they lost 5 HP with fine Vs. fat wire plugs.

[user-23911]

When you change plugs or plug gaps, you need to also adjust the timing advance to compensate.
Like pretty much everything to do with tuning.....change one thing and it affects other things.

[jacksoni]

This paper is an interesting read: http://papers.sae.org/2006-01-0224/

I am aware of other private testing similar that showed that the big plug used in top fuel cars had a better kernel than smaller fine point plugs.

[pdq67]

twl wrote:
"Gapless" racing spark plug. I think it's NGK.
Image

Well, it keeps stupid out of setting the gap.

I love it!!

"keeps STUPID out!!"....

He, He!!

pdq67

[af2]

Gawd I hope my Uncle never reads this because it will take 3 hours to set up 3 sets of plugs on his blown Alky deal..........

[jake197000]

as long as all your parts are good and you have a GOOD coil your golden.

[n2omike]

Another 'thread from the dead'...

I always liked seeing Big Joe chime in with pure experience. Lots of keyboard scientists out there saying what 'should' happen, and then there was Joe who would simply test things instead of doing a theoretical research paper on them. He can tell you the fine wire plugs lose 'X' amount of power, etc... and people would argue with him, and get into a big scientific discussion. Guys like him are pioneers. They try more stuff than most people would ever think of, and find what works. They are the first to do so... and then the rest come in and try to figure out WHY.

I do find the idea of rounding off the sharp edges of spark plug electrodes interesting. Seems like a great idea on something detonation prone.

[FredWinterburn]

But if Joe used the same gap with the fine wire plugs as he did with a conventional plug (assuming the same resistance), then yes the spark power would be lower because the voltage threshold would have been lower. Had he opened up the gap a few more thou with the fine wire plugs, I'll bet he would have made more power. Testing has to include all of the variables and in this case having the same gap introduces another variable, not a constant. Fred

Another 'thread from the dead'...

I always liked seeing Big Joe chime in with pure experience. Lots of keyboard scientists out there saying what 'should' happen, and then there was Joe who would simply test things instead of doing a theoretical research paper on them. He can tell you the fine wire plugs lose 'X' amount of power, etc... and people would argue with him, and get into a big scientific discussion. Guys like him are pioneers. They try more stuff than most people would ever think of, and find what works. They are the first to do so... and then the rest come in and try to figure out WHY.

I do find the idea of rounding off the sharp edges of spark plug electrodes interesting. Seems like a great idea on something detonation prone.