Check my plugs, please....(again)

[Ironmike]

Hi guys! Switched from NGK B6... to AC 3923. Same heat range. Seems to actually run a tad better. Nice idle at 1200, quick start...all good.

Last night did a 6800 RPM key off, clutch in and checked No. 1. Drove 2 miles home, not a lot of idle time and checked No. 1 again. Surprised to find that it looked EXACTLY like it did after my shutdown check. If I look down ito it with a flashlight and mag glass i'm pretty sure the porcelain is white clear to the bottom.

Took a few pics, all the same plug and wanted to know what you all think. I built my motor, tune it and everything else, but i dont think my plug checking is all that great.

MY guess would be up 2 jet sizes.....but hoping you all could give me your opinion. PLEASE don't even mention timing, if possible. I'm locked out at only 30 degrees and that's where it wants to be.

Hoping YR and Rusty will chime in, in addition to anyone else. Those guys seem to know their plugs....

 

[hotrod68]

looks to me like jetting it up is a good idea, but I'm no plug expert either.

 

[rmchrgr]

The center pic looks OK. The flash is making the strap look lighter than it is. Should usually see a little brown/tan on the porcelain but kind of just a dusting. Is there an issue? Or are you just looking for a 'perfect' plug? Do you have an A/F gauge?

You say don't mention timing but why? Locked at 30 degrees seems odd, it's pretty conservative. If it's a small block, should be at least 34, big block likes more. Not sure how you arrived at 30 degrees, perhaps you could explain that. You could be chasing your tail trying to tune it at 30 degrees when you might see different results with more timing.

But since you don't want to talk about it, more fuel is not going to do anything for it.

 

[Ironmike]

No issues. Right now the thing is just a flat out beast. Just wasn't sure if it's running "dangerously" lean. Like to get real close on the fuel until I can get to the track. 30 degrees seemed really odd to me too, but the dyno told me so. Pretty extensive dyno time in February or March. I was pretty surprised at that number. Lost 18HP going to 33 and more at 35. Dyno guy was NOT surprised at all.

No a/f gauge. Not a fan. Eventually MPH will sort it out, just can't get to the track until July. Friggin work......

 

[AJ/FormS]

Aluminum Heads and tight Squish?

Your engine sound like a monster.
My little 367 with Eddies and .035 squish also likes minimal timing. It's never been dyno'd, but time trials showed that it didn't care about timing over 32*. It was no faster/no slower. So I run 32*. I also run 87E10, in those chambers@ 10.7Scr/8.7Dcr

 

[rmchrgr]

I dunno, something is not right about 30 degrees. I understand you have 'hard evidence' but it just seems very conservative. If you have really a efficient combo I guess but even then seems hard to comprehend that a few more degrees of timing would cause a LOSS in horsepower. If it were me, I would question that logic and see what happens if you add some timing. You may not see it on a dyno sheet but your seat of the pants dyno might tell you different. Almost every engine I have ever messed with benefited from more timing. Just thinking out loud, YRMV.

Anyway, if it is a beast then why mess with it? Get a baseline at the track then go from there. Jet for MPH and keep going until mph falls off. If you add more fuel, you may need more timing. Though it may seem contrary to conventional wisdom, lean makes power.

I see you are in PA so July will naturally be hot and humid. Of course your tuning results in July will be different than what they would be in the cooler spring or fall.

Also, why not a fan of an A/F gauge? I find they are very helpful. I have them in both my vehicles. I gained some mileage on my overcammed, low compression truck tuning with an A/F gauge. It's great for tuning things like part throttle operation. It also really helps to see an overall picture of a pass down the track from start to finish, especially with a data logger type. It's just a tool.

 

[IQ52]

Unleaded fuel? If so, on new plugs there should be a light gray fuel ring about 1/16" wide at the base of the porcelain and the rest of the porcelain should be white.

 

[MOPAROFFICIAL]

The center pic looks OK. The flash is making the strap look lighter than it is. Should usually see a little brown/tan on the porcelain but kind of just a dusting. Is there an issue? Or are you just looking for a 'perfect' plug? Do you have an A/F gauge?

You say don't mention timing but why? Locked at 30 degrees seems odd, it's pretty conservative. If it's a small block, should be at least 34, big block likes more. Not sure how you arrived at 30 degrees, perhaps you could explain that. You could be chasing your tail trying to tune it at 30 degrees when you might see different results with more timing.

But since you don't want to talk about it, more fuel is not going to do anything for it.

For your average build "most run lower than desired cylinder pressure" you are correct in that 30 degrees is low, but with matched compression to the octane 30 is sweet and expected. I only run 28 degrees total but i have 185 psi dynamic w/10.1 static.
If i were ironmike i would get some NGK plugs, they are easier to read, and depending on the cranking psi. ..he might want to try some 1233's #BPR5EY plugs that are a step colder than a gr4 replacement.

 

[MOPAROFFICIAL]

I dunno, something is not right about 30 degrees. I understand you have 'hard evidence' but it just seems very conservative. If you have really a efficient combo I guess but even then seems hard to comprehend that a few more degrees of timing would cause a LOSS in horsepower. If it were me, I would question that logic and see what happens if you add some timing. You may not see it on a dyno sheet but your seat of the pants dyno might tell you different. Almost every engine I have ever messed with benefited from more timing. Just thinking out loud, YRMV.

Anyway, if it is a beast then why mess with it? Get a baseline at the track then go from there. Jet for MPH and keep going until mph falls off. If you add more fuel, you may need more timing. Though it may seem contrary to conventional wisdom, lean makes power.

I see you are in PA so July will naturally be hot and humid. Of course your tuning results in July will be different than what they would be in the cooler spring or fall.

Also, why not a fan of an A/F gauge? I find they are very helpful. I have them in both my vehicles. I gained some mileage on my overcammed, low compression truck tuning with an A/F gauge. It's great for tuning things like part throttle operation. It also really helps to see an overall picture of a pass down the track from start to finish, especially with a data logger type. It's just a tool.

Flame travel is quick with closed chamber and the mix is atomized pretty hard as well leading to a faster more complete burn-fast burn need less advance timing, setting it off too soon hurts power about as mush as lighting it too late. Octane also dictates the timing outcome. I know some of my stuff only needs 25 total...

 

[Ironmike]

.031 squish. 190 psi cranking compression, warm. Seat of pants to me seems like the dyno is right. My best seat of pants test is how quick my shift light comes on in 3 rd gear......at 30 degrees, best be ready to slam 4th real quick.

As I said I WAS running NGK BK6RE. ....didn't really like em....

 

[nm9stheham]

Unleaded fuel? If so, on new plugs there should be a light gray fuel ring about 1/16" wide at the base of the porcelain and the rest of the porcelain should be white.

This is what (I think) I have been recently learning with modern pump fuels... the old plug colors well up on the porcelain don't apply. Ironmike, you'd do yourself a favor to get an AFR meter. Yeah, I know it seems like cheating for a good old fashioned carbed engine, right? But I threw in the towel on that matter recently LOL. As well said, it is a tool.

 

[MOPAROFFICIAL]

.031 squish. 190 psi cranking compression, warm. Seat of pants to me seems like the dyno is right. My best seat of pants test is how quick my shift light comes on in 3 rd gear......at 30 degrees, best be ready to slam 4th real quick.

As I said I WAS running NGK BK6RE. ....didn't really like em....

Mike the BK6RE is too cold, you would scratch your head at the diff between the 2 if you tried the "5's" instead. Ironic that i just did this same dance.. gr4 too hot, 6 too cold .......5's just right. Ps i too have .030 quench, with iron.

 

[AJ/FormS]

There you go; 190 and .031.
I did run 185 and .020 for one summer.I chickened out, and backed things up; it's just a streeter.

 

[yellow rose]

I didn't read every post in this thread. I wanted to say that first.

Again, for the umpteenth time (and RRR says that is a lot of times) you can NOT read a plug with a BLACK shell. It is IMPOSSIBLE.
There are several reasons why I only use champion plugs. Number one is the numbering system. Number two is how they determine heat range. Number three, and almost most important, is the coating they use on the plug. I know how much heat I have in the chamber. NGK uses a totally different coating, and they range their plugs differently than champion. Also their plug numbering system is out of control.

All that said, I have no real way of telling you what you want to hear. You have to have a plug that is readable. That one isn't.
I know there are web sites with pictures and definitions and lots of how to theory, but that plug won't tell you all you need to know.

As you look at the plug nose, the end closest to the ground wire is cruise fuel, as you move down the plug core, you are looking at transition and mid range tuning. This is especially important on road course cars. The bottom of the core, where it goes into the shell, is where you read WOT.

Get a better plug. Take pictures with more view of the core down near the shell.

 

[rmchrgr]

The one thing I have to say about tuning by looking at plugs is it's pretty useless unless you put brand new plugs in before a pass with as minimal idle time or cruising through the pits as possible. Pull to the line, make your pass, shut it off immediately after the stripe, coast to the return road and pull the plug. That's the only accurate way.

Other than that, an A/F gauge is the best way to tune. You won't even have to pull the plugs except to verify the tune.

 

[Ironmike]

What Champion would a guy run with 11 to 1 (10.75, really)and a 5/8 socket size?

 

[rmchrgr]

 

[justinp61]

Good information, Ron posted it on Moparts about two weeks ago.

 

[MOPAROFFICIAL]

NGK plug charts are sometimes hard to read when you pick up the book, but the plugs are top notch and unlike champion...the insulators don't come loose and do the Boogaloo in the cylinders. As for the coating being different, idk what say to something so outlandish...but what do i know. I say just use a plug with a nickle plating or just non black.
2-3 threads of color change, timing marks at apex of ground strap and some grey to tan color down near the base of porcelain where it meets the case. As long as you dont have soot around the base ring and have all the rest mentioned....you're close to sweet.

 

[yellow rose]

NGK plug charts are sometimes hard to read when you pick up the book, but the plugs are top notch and unlike champion...the insulators don't come loose and do the Boogaloo in the cylinders. As for the coating being different, idk what say to something so outlandish...but what do i know. I say just use a plug with a nickle plating or just non black.
2-3 threads of color change, timing marks at apex of ground strap and some grey to tan color down near the base of porcelain where it meets the case. As long as you dont have soot around the base ring and have all the rest mentioned....you're close to sweet.

I don't make **** up friend. NGK uses a different finish, and it translates to different plug temps.

Pick up a book and learn. It's published knowledge.

 

[yellow rose]

The one thing I have to say about tuning by looking at plugs is it's pretty useless unless you put brand new plugs in before a pass with as minimal idle time or cruising through the pits as possible. Pull to the line, make your pass, shut it off immediately after the stripe, coast to the return road and pull the plug. That's the only accurate way.

Other than that, an A/F gauge is the best way to tune. You won't even have to pull the plugs except to verify the tune.

Horsecrap. I can look at plugs you have been driving on for many miles and probably get you closer than you are on tune up.

I don't spend my money on new plugs unless I am down to WOT tests and I am looking at the fuel ring.

In fact, I can tell you at the track on night I had to prove this to a friend who had a junk converter. I forget how many runs he made, but it was a bunch. We moved the timing from 34 to 42 in 2 degree increments. Every run you could see the plugs change. Then we went 4 sizes leaner on jet. In one run the fuel ring closed up. Went to 4 sizes bigger than we started. Fuel ring fattened up. And the car NEVER varied more than .1 in ET and less than 1 MPH. The converter was JUNK.

The point is, you could see every change, every time, every run on the same plug.

 

[yellow rose]

What Champion would a guy run with 11 to 1 (10.75, really)and a 5/8 socket size?[/QUOTE

Aluminum head RC12YC
Iron head RC9YC

You are on the edge of both plugs. Meaning the 12 might be a touch hot, but the 9 might be a bit cold.

I'd rather be a touch hot, and tune around it that be fouling plugs. On the other hand, I have been in the spot where a 12 was so hot it would idle fine, but when using the throttle it would miss. Put a 9 in it and it's still going today.

 

[rmchrgr]

Good information, Ron posted it on Moparts about two weeks ago.

That's where I got it.

I will admit that there is more to plug reading than meets the eye and it's not completely useless like I originally said. However, I still maintain an A/F gauge will give you mostly accurate, real time results and can make life easier. If you have a sophisticated tool at your disposal, why choose not to use it?

There are so many variables involved in tuning a carbureted engine with pump gas, it's not just checking plugs. Everyone knows different days give different readings, your tune could be good for one day then the humidity goes up and everything goes out the window. Besides, there is enough alcohol in pump gas to skew things lean.

In addition, modern electronic ignitions like an MSD are much more efficient than older types, it's like night and day sometimes. Even if your tune is off, the plugs can still look OK.

I also will reiterate that reading anything but a new plug after a single WOT run is the most valid method of reading plugs. Read anything you can find, it's usually the first thing mentioned.

 

[AJ/FormS]

Since we're not in the racers forum, I guess I can sound off:
The same 12s have been in my 367 since about 2004, for around 80,000pus miles. I can't say if that is good or bad, but the big square Accell SuperCoil keeps lighting them, so I guess they can stay in there a little longer.I think I mighta read the plugs a time or two,back in the beginning. Shes a streeter, and at just over 400hp, she rarely has to pull hard enough to have to be running on the edge. That's one of the reasons I like 360s,they got pretty good grunt. I know that if I had less motor I'd be a lot more concerned.
I just leaned out the mains 'til she bucked, and gave her a tad back. Then I leaned out the idle circuit, til she wouldn't take it anymore.Then I gave her vacuum advance til she stopped whining. When she gave me back 32 mpgUS I figured that was lean enough.In a moment of generosity, I gave her a little fuel back. Bin like that ever since.(750DP-AG)
IDK, .............A streeter can be way off tune and run just fine.
I mean first gear is usually good to about 60 mph, and you're mostly spinning the whole way, so the engine is never hardly loaded. She'd have to be pretty far off to tell you about it.
IDK,I just don't get all the carburetor hullabaloo for streeters
I mean I understand if you have a drag car. Those guys need to run spot on.But they are operating in a pretty narrow window.Streeters,on the otherhand,are all over the place.To me, getting the tune from 2000 to 4000 under a multitude of different loadings, is vastly more important. And here plug reading isn't even hardly on the table. Here a wide-band can save many many hours out of futzing.
IDK, maybe I'm just lazy...........

 

[rmchrgr]

To me, getting the tune from 2000 to 4000 under a multitude of different loadings, is vastly more important. And here plug reading isn't even hardly on the table. Here a wide-band can save many many hours out of futzing.

Kind of what I am saying here...