Appreciate some input on spark plug reading

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First you said your (US) pump gas doesn't colour plugs and it must be an Australian fuel thing:

Newbomb Turk said:
Not on US pump gas. He’s not down under is he?
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Clearly all those plugs in post #18 that are from US cars are running US pump Fuel magically show colour when you claimed they can't or won't

Now you want to claim that race fuels don't colour plugs either? You can't seem to keep up with you're own claims.

Demonx2 said:
Remember this is on pump 93 fuel.
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Try a lower octane pump fuel. The reason your plug is white on the porcelain is its LEAN AT TIME OF IGNITION AT THE SPARK PLUG! It doesn't matter what AFR you give the cylinder in total its the AFR AT THE SPARK PLUG THAT MATTERS. In your case its LEAN, even though the rest of the cylinder can be really rich. Just because your carb meters an AFR of 12.8 that doesn't mean that's what it is through out the cylinder.
 
The problem I see with plug reading is that the plug can see a variation in operating conditions throughout the rpm range, especially on street cars that are drag raced. How long [ in seconds ] does it take to 'colour' a plug? What good is it if the colour is 'right' after a WOT run, but the plug fouls [ & loses time ] at idle & lower rpms because it is too cold. I believe too many people run colder plugs than the engine wants/needs. Wrap some alum foil into a shape of a cigarette & hold a lighter under it. Gets too hot to hold very quickly! Now hold the lighter under a 650 lb cyl block & heads. You will be waiting for ever for it to heat up.......
My point is: how quickly can the plug heat up during a 11-12 sec 1/4 mile run with 650 lb hunk of metal also absorbing the heat. I would stick with the heat range that the manufacturer designed & tested for. I can think of only a few instances where a colder plug would be needed. A hotter plug might be needed with a worn engine.
 
Hysteric said:
First you said your (US) pump gas doesn't colour plugs and it must be an Australian fuel thing:



Clearly all those plugs in post #18 that are from US cars are running US pump Fuel magically show colour when you claimed they can't or won't

Now you want to claim that race fuels don't colour plugs either? You can't seem to keep up with you're own claims.


Try a lower octane pump fuel. The reason your plug is white on the porcelain is its LEAN AT TIME OF IGNITION AT THE SPARK PLUG! It doesn't matter what AFR you give the cylinder in total its the AFR AT THE SPARK PLUG THAT MATTERS. In your case its LEAN, even though the rest of the cylinder can be really rich. Just because your carb meters an AFR of 12.8 that doesn't mean that's what it is through out the cylinder.
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Easy there slick. I never said you can’t get color on a plug here. I said it’s a power loser. Every time.

Try again and see if you can peddle more bullshit.
 
Bewy said:
The problem I see with plug reading is that the plug can see a variation in operating conditions throughout the rpm range, especially on street cars that are drag raced. How long [ in seconds ] does it take to 'colour' a plug? What good is it if the colour is 'right' after a WOT run, but the plug fouls [ & loses time ] at idle & lower rpms because it is too cold. I believe too many people run colder plugs than the engine wants/needs. Wrap some alum foil into a shape of a cigarette & hold a lighter under it. Gets too hot to hold very quickly! Now hold the lighter under a 650 lb cyl block & heads. You will be waiting for ever for it to heat up.......
My point is: how quickly can the plug heat up during a 11-12 sec 1/4 mile run with 650 lb hunk of metal also absorbing the heat. I would stick with the heat range that the manufacturer designed & tested for. I can think of only a few instances where a colder plug would be needed. A hotter plug might be needed with a worn engine.
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A plug can overheat in a fraction of a second. Once it’s overheated you have to remove the heat source to get the plug temperature back down.
 
Hysteric said:
First you said your (US) pump gas doesn't colour plugs and it must be an Australian fuel thing:



Clearly all those plugs in post #18 that are from US cars are running US pump Fuel magically show colour when you claimed they can't or won't

Now you want to claim that race fuels don't colour plugs either? You can't seem to keep up with you're own claims.


Try a lower octane pump fuel. The reason your plug is white on the porcelain is its LEAN AT TIME OF IGNITION AT THE SPARK PLUG! It doesn't matter what AFR you give the cylinder in total its the AFR AT THE SPARK PLUG THAT MATTERS. In your case it’s LEAN, even though the rest of the cylinder can be really rich. Just because your carb meters an AFR of 12.8 that doesn't mean that's what it is through out the cylinder.
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There’ s a bunch of fuzzy thinking here. You believe that the fuel distribution throughout the cylinder at time of ignition is vastly different? “Try a lower octane” octane is burn rate. What is burn rate going to do for AFR. I’m trying man, but I can’t remember anyone saying the color of plugs is not informative. Just that vastly different fuels will color them differently.
 
fishmens67 said:
I'd try a one step hotter plug.
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You need to get a plug flashlight/magnifier that lets you look at the bottom of the ceramic for accurate plug reading. That way you won't have to cut off the threads. Just looking at the photos you posted, I'd say that you are running very rich. What jets do you have in the carb?
barry91765 at g male
 
furrystump said:
You believe that the fuel distribution throughout the cylinder at time of ignition is vastly different?
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Yes it can be. It also varies between induction strokes and varies between cylinders in some cases as much as 11-1 to 17-1.
furrystump said:
“Try a lower octane” octane is burn rate.
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Its the vaporization rate not the octane. Lower octane fuels are designed to vaporize in low compression engines. If its lean at time of ignition you haven't converted enough of the fuel to a gas state around the plug for it to get the process started efficiently. You only burn what transforms from a liquid state to a gas state. Notice those stocker plugs all had colour on them? The OEMs spend billions to get the combustion right.

If you 6-8 jet sizes up what will your plugs look like then? Black right, so its now rich because you flooded the chamber but if its white its not lean?
 
Newbomb Turk said:
Easy there slick. I never said you can’t get color on a plug here. I said it’s a power loser. Every time.
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Great, since you know so much you shouldn't have any problem answering these questions, can you tell me what Stoichiometry is?
 
Hysteric said:
Great, since you know so much you shouldn't have any problem answering these questions, can you tell me what Stoichiometry is?
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I can. But I won’t. Why bother? You can’t learn how wrong you are. And it’s not just me trying to tell how screwed up you are.

Plus you lie or you just make **** up. I called VP fuels. You got caught on that one.
 
Newbomb Turk said:
I can. But I won’t. Why bother? You can’t learn how wrong you are. And it’s not just me trying to tell how screwed up you are.

Plus you lie or you just make **** up. I called VP fuels. You got caught on that one.
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Why are you scared to answer a simple question.........

Did VP fuels tell you their fuels don't colour plugs too......
 
Newbomb Turk said:
No.
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Then answer it......You make bold claims but when it comes down to the crunch you avoid answering a simple question. Why would you be scared to answer a simple basic question?
 
Hysteric said:
Its called Chemistry.
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No ****??? I'm not talking about that. I know exactly what it is and how ignorant your ways of tuning are.

Better men than me have looked at your posts on here. Their conclusions are the same as mine.

Take that for what it's worth as you are unable to accept you are wrong. And it doesn't have anything to do with stoichiometry.
 
Newbomb Turk said:
lol. Keep trying. I don’t answer your questions.
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That's because you can't......

Here's a really good thread on tuning. Tom Vaught was an Engineer at Holley and quoting Shrinker so would know more than the experts here. Start at post #150

SOME HOLLEY CARB TIPS PONTIAC forum

Some key take aways: testing was on a tunnel rammed 400 ci race engine.

"When I say to you guys that a particular engine hasn't got enough vaporization that is what I'm commenting on. How it looks inside the cylinder is like this, the AFR at ignition time is leaner than the average of the cylinder, lets say the average is 12.8 but at ignition time the AFR around the plug is AFR 14, the flame is going to grow slow and some of the flames energy is going to used in vaporizing the fuel thats not gas yet. So the flame kernel doesn't generate enough heat and you dont get a TAN plug, you also run the risk of extinguishing the flame if turbulence is poorly directed.

The burn time determines the peak cylinder pressure. Its the peak pressure that is one of the principle determining factors for the production of CO into CO2. If its not high enough you wont get the conversion underway so the exhaust contains high values of CO. If the CO is produced with a high oxygen consumption then the exhaust stream will be low in O2.

Now a WB theorist will tell you that the WB will use the unused O2 to convert the CO into CO2 etc and complete the burn to perfection and report a result. Well that's correct but the reality of this type of burn is that the O2 is used to make excess CO and forgo the conversion to CO2 because it just didn't get hot enough for long enough. This type of burn is far from correct as the theory books only want to consider.

There isn't the normal correct balance of O2 to CO of a rich burn. The CO2 levels are low and the WB catalyst needs the CO2 to break it apart and get some O2 to reform the CO to CO2, the reaction of which is O2 neutral. So the WB has to get the O2 from the outside air and that causes it to report a high O2 requirement thus richer than truth."

(The Late and Great Bruce Robertson AKA Shrinker!)

"So in simple Tom Vaught terms:

Learn how to read Plugs and don't trust the Air/Fuel Meter to be the Final Word on the Air/Fuel mixture going on inside the engine.

Tom V."

"Some can read them better than I can, but I am ok on the electrode and a bit down on the insulator. Shrinker was a PRO, (I was told) on that deal.
But again I am just posting suggestions to this thread (Not making assumptions based on just one piece of information from one piece of equipment.)

Tom V."

Oh and Tim let me know when you're Carbs are on and tuning Pro Stock engines I'll gladly sit at your feet to learn what you have figured out.
 
Hysteric said:
That's because you can't......

Here's a really good thread on tuning. Tom Vaught was an Engineer at Holley and quoting Shrinker so would know more than the experts here. Start at post #150

SOME HOLLEY CARB TIPS PONTIAC forum

Some key take aways: testing was on a tunnel rammed 400 ci race engine.

"When I say to you guys that a particular engine hasn't got enough vaporization that is what I'm commenting on. How it looks inside the cylinder is like this, the AFR at ignition time is leaner than the average of the cylinder, lets say the average is 12.8 but at ignition time the AFR around the plug is AFR 14, the flame is going to grow slow and some of the flames energy is going to used in vaporizing the fuel thats not gas yet. So the flame kernel doesn't generate enough heat and you dont get a TAN plug, you also run the risk of extinguishing the flame if turbulence is poorly directed.

The burn time determines the peak cylinder pressure. Its the peak pressure that is one of the principle determining factors for the production of CO into CO2. If its not high enough you wont get the conversion underway so the exhaust contains high values of CO. If the CO is produced with a high oxygen consumption then the exhaust stream will be low in O2.

Now a WB theorist will tell you that the WB will use the unused O2 to convert the CO into CO2 etc and complete the burn to perfection and report a result. Well that's correct but the reality of this type of burn is that the O2 is used to make excess CO and forgo the conversion to CO2 because it just didn't get hot enough for long enough. This type of burn is far from correct as the theory books only want to consider.

There isn't the normal correct balance of O2 to CO of a rich burn. The CO2 levels are low and the WB catalyst needs the CO2 to break it apart and get some O2 to reform the CO to CO2, the reaction of which is O2 neutral. So the WB has to get the O2 from the outside air and that causes it to report a high O2 requirement thus richer than truth."

(The Late and Great Bruce Robertson AKA Shrinker!)

"So in simple Tom Vaught terms:

Learn how to read Plugs and don't trust the Air/Fuel Meter to be the Final Word on the Air/Fuel mixture going on inside the engine.

Tom V."

"Some can read them better than I can, but I am ok on the electrode and a bit down on the insulator. Shrinker was a PRO, (I was told) on that deal.
But again I am just posting suggestions to this thread (Not making assumptions based on just one piece of information from one piece of equipment.)

Tom V."

Oh and Tim let me know when you're Carbs are on and tuning Pro Stock engines I'll gladly sit at your feet to learn what you have figured out.
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Way to copy and paste what you can’t put in your own words.

I know exactly who Mr. Vaught is.

Let me know when you can use your own words like a 6th grader.

How many Pro Stock carbs have YOU tuned?

Or better yet, how about you tell us what YOU’VE done rather than living vicariously through other people you clown.
 
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