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Methanol Plug Reading

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Methanol Plug Reading

Postby jaded13640 » Fri Sep 07, 2012 1:55 pm

Hi,
When reading spark plugs when using methanol you don't go by the color of the porcelain you go by the heat line going up the threads.
As I recall "perfect" is 3 threads up.

The problem I'm having is that the plugs I've been using all along, NGK R5672A-8's don't seem to have the same gold colored irritation on them and the heat line isn't showing up.
No matter how rich or lean I've run it it's not showing color on the threads.
I've even tried wire brushing the threads in an attempt to remove whatever coating might be on there so I could get a reading but no love.

I'm using a "130" Enderle pill which is what I've always used so I know I'm close but, again, no heat line.
I've tried a 125 and a 135 just to see if something would show up on the threads but nothing.

I also have an EGT system but that only works if you're already pretty close to your fuel tune.
You can be overly rich and the EGT will read high because the fuel is burning in the tube where the EGT probe is.

This is a NA application.

Any thoughts?
Maybe a different brand or type of plug for tuning?

I'm sure Dave Kohler could advise if he's not still too mad at me.

Thanks,

Wayne
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Re: Methanol Plug Reading

Postby ProPower engines » Fri Sep 07, 2012 2:24 pm

On an engine thats close to right going from a 135 to a 125 was brave [-o<
I have had the same issue and if it were me I would change plug brands to make reading them easier.
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Re: Methanol Plug Reading

Postby BrazilianZ28Camaro » Fri Sep 07, 2012 4:40 pm

I'd forget the plugs and watch the MPH, going richer a little at time until the car slow down. Then come back a step.

I can't see how this could hurt your engine. Remember the only number that proves your engine is doing well is the E.T.
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Re: Methanol Plug Reading

Postby jaded13640 » Fri Sep 07, 2012 5:28 pm

ProPower engines wrote:On an engine thats close to right going from a 135 to a 125 was brave [-o<
I have had the same issue and if it were me I would change plug brands to make reading them easier.


ProPower,
130 was what the spreadsheet called for and seemed to be running fune, I stepped up (richer) one pass and went slower so I needed to then step one step leaner.
I actually had an issue and never actually ran down the track with the leaner pill...Providence maybe? LOL

Great advise on the changing plug brands to make readin easier.
Any sugestions on a different brand?
I'm kinda bummed because I really like NGK'.
They make a really good quality plug and they're considerably less expensive to boot.



BrazilianZ28Camaro wrote:I'd forget the plugs and watch the MPH, going richer a little at time until the car slow down. Then come back a step.

I can't see how this could hurt your engine. Remember the only number that proves your engine is doing well is the E.T.


Brazilian,
Though I agree that the best E.T. and MPH are the signs of a correct tune but I believe that proper plug reading is crutial for tuning a methanol motor.
Not only does your plug reading tell you if you're getting close it'll tell you where you're at with your timing and can present signs of issues before things go bad.
One time I was running good, consistant and checked them between two round just out of couriousity and because I hadn't checked them in 3 passes..
The heat line went north by at least 2 threads!
Without changing my E.T. more than a few thousandths!
It turned out that there was some debris in that hole's nozzle.
Had I gone another pass or possibly two there's a good chance I would have burned a pistons.
At that time I had been reading the plugs every three passes or so.
Now the ONLY time I skip reading them if I'm going rounds and they Force us to hot lap.

It seems to me a heat line should show up on any plug.

Did NGK start using a different material?
Did they change to a different coating or eliminate it?
Can anyone recommend another brand that would be more applicable?

Any help would be appreciated greatly,

Thanks,

Wayne
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Re: Methanol Plug Reading

Postby BrazilianZ28Camaro » Fri Sep 07, 2012 5:41 pm

I do understand what you saying Wayne, but the reading the AFR by the heat absorption/ discoloration of the plugs have much more variables involved than a single number (MPH).

You know the methanol at 120 iso-octane is almost impossible to detonate, and it burns rich, real rich, naturally some will burn at the exaust.

As you stated,lean AFR is where the $hit happens, so what if the plugs say the AFR is ok and your AFR might actually be lean?

If was my car, I'd set the fuel and timing by the best MPH and record the EGTs. Anything different than the number you have might indicate problems.

JMHO
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Re: Methanol Plug Reading

Postby FC-Pilot » Fri Sep 07, 2012 5:42 pm

I use Autolite racing plugs, but a number of the guys I race against use NGK's. The coating on the NGK plugs is considered one of the best for reading. I use Autolites because that is what I am used to. But it has to be their race plugs as the standards do not have the coating which makes it easier.

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Re: Methanol Plug Reading

Postby ProPower engines » Fri Sep 07, 2012 6:16 pm

Something tothink about is when looking at colder plugs for racing concider 2 stroke engine spark plugs.
They can be had quite cheap. The coating on the NGK plug does make it easier to read the heat line but that said look at the 2 stroke plugs.
I have been doing that for 25yrs with out issue. I talked to Smokey Y about champion race plugs years back and he put me onto the 2 stroke plug idea. Back then there was no race plug persay for old double bump heads but a J4c outboard plug with a 13/16 gasketed plug fit perfectly and was readily available. =D>
Just something to think about when not in the box :D
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Re: Methanol Plug Reading

Postby jaded13640 » Sat Sep 08, 2012 5:23 pm

FC-Pilot,
Thanks for the tip on Autolites.
So their "race grade" of plugs DO have a coating?



Pro,
Do you have a brand in mind?

Are two cycle plugs "resistor" or "non-resistor" or are they available in both?
How would I know what heat range would be applicable?
Can you point me to any info regarding this?

I don't care what plugs I use, I just need to be able to read them.

Are you aware of a brand or grade that has a coating like NGK used to?

Is anyone familiar with NGK's?
Do other grades of NGK's still have the coating?

Can anyone else recommend another brand that has a coating?

Thanks,

Wayne
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Re: Methanol Plug Reading

Postby noice » Sat Sep 08, 2012 8:22 pm

I run open headers and only when I shift the powerglide do I ever see a flame come out of the exhaust. I don't think your idea of the EGT's not being accurate is right. I try to keep it at 1200F in the 1/4 mile and I record the highest temperature hit in the run. If you really need to tune it correctly, get an O2 meter and calibrate it to methanol and run it to like .90 lambda.
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Re: Methanol Plug Reading

Postby Dragsinger » Sat Sep 08, 2012 8:43 pm

http://www.killerrons.com/15.cfm

might be some helpful info in this link
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Re: Methanol Plug Reading

Postby FC-Pilot » Sat Sep 08, 2012 11:55 pm

Yes, the Autolite race plugs DO have a coating similar to the NGK's.

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Re: Methanol Plug Reading

Postby ProPower engines » Sun Sep 09, 2012 1:16 am

Pro,
Do you have a brand in mind?

Are two cycle plugs "resistor" or "non-resistor" or are they available in both?
How would I know what heat range would be applicable?
Can you point me to any info regarding this?

I don't care what plugs I use, I just need to be able to read them.
Wayne[/quote]

Champion has a silver coating and are non resistor
NGK has both resistor and non resistor and a silver or gold coating.
Autolite are black and hard to read the thread heat line
If you can find a Bosch spark plug cataloge it has an interchange of sorts in the back.
It will list wether or not its a resistor plug and the reach/thread length and size as well as the hex size and tapered or gasketed seat. Then it has a cross over to other brands. It sort of allows you to design a plug style and heat range and put a part number to it so the dummy at the auto supply can acually see and order them for you.
Been doing it that way for 25yrs. Its very helpful when you have tight areas to get plug wires on the plug.
You know those real short plugs on lawn mowers that are about 1 1/2" total length they really do fit a stock double bump head.The work great when space is tight or the header tube is close to the plug boot and burns them up.
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Re: Methanol Plug Reading

Postby jaded13640 » Sun Sep 09, 2012 2:35 am

noice wrote:I run open headers and only when I shift the powerglide do I ever see a flame come out of the exhaust. I don't think your idea of the EGT's not being accurate is right. I try to keep it at 1200F in the 1/4 mile and I record the highest temperature hit in the run. If you really need to tune it correctly, get an O2 meter and calibrate it to methanol and run it to like .90 lambda.


Noice,
I'm not talking about flames coming out of the end of the exhaust.
What I said was, "You can be overly rich and the EGT will read high because the fuel is burning in the tube where the EGT probe is.
The probes are usually placed between 1 1/2" to 2" from the flange.
Mine are 2 inches from the flange.
Ordinarily if your temp is a little high you're a little lean and can adjust accordingly.
But if you're mixture is overly rich you'll see excessive heat at the probe.
In that case if you were going by EGT's alone you'd assume lean, tune it richer, further compounding the error.
That's what I was talking about with that guy from Texas with the Ron's system.
He refused to acknowledge that the plugs are read differently with methanol than gas and insisted it was lean when in fact it was rich.
He kept fouling plugs, eventually washing down the cylinders, gave up and sold the Ron's system.

I also set my EGT monitor to read the max temp on a pass.
My old motor seemed to like around 1175F or so but that had a full 2.5 points of compression higher and had domed pistons.
With the 130 pill in the fuel system this motor was running around 1200F.

Is anyone out there using an O2 sensor with methanol?

I seem to remember there's a problem there...I think there's an issue because of the oxygen that's already in the fuel but I'll look into it.
I looked into it before and but it seems to me there was an issue.
If I remember correctly that's why I didn't pursue it any further.
But, again, I'll look into it some more.

Thanks.

Dragsinger,
Thanks for the link.

Paul,
Thanks for the info on the coating on the Autolites'

ProPower,
Great stuff,
I'm not sure why NGK eliminated the gold coating on the grade I use.
I'll look for a Bosch catalog, sounds like a great resource.
Amen to "dummy at the auto parts store" comment.
I call it the "fast food autoparts" phenomenon...
Very cool on the lawn mower plug.
I never would have guessed that would work.
I've actually got one boot closer to the primary than I would like.
My chassis was built around a hemi.
Since I run a wedge I had to build my own headers and that's just the best I could do for that port.
I made the mistake of "bigger is always better" thinking and made the zoomies out of 2 1/2" diameter tubing! LOL
1/4" smaller would have made life way easier and cheaper but man do they look impressive. LOL
I built them with my little mig welder but I ground all the welds flush.
People will ask how I managed to get all those contours in one piece.
I even welded a Hooker Header tag on them to further confuse people.
It worked, more than once I was ask what part number that "set" was. LOL
Thanks,
Good stuff.

Anyone else want to chime in?
Like maybe a mechanical fuel injection expert?
Do we have anyone on this forum who has a mechanical fuel injection business?
Hmmmm...seems to me we have someone on the forum who was in that line of work...
Hmmmm...
But at least my push rods are right...
LOL
Let's let bygones be bygones. I acknowledged you were right.

Thanks guys,

Wayne
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Re: Methanol Plug Reading

Postby RednGold86Z » Sun Sep 09, 2012 8:01 am

I use methanol in OEM applications - here's a few things:

1) When using a wideband system, it works the same no matter the fuel - if you leave it set for gasoline. I.e. if you want lambda 1 (all fuel and air consumed), it'll show 14.7 (even though it's actually getting about 6.45:1). If you want lambda 0.8 (which I recommend for methanol WOT as a starting point until you figure out the plug heat range), it should read about 11.76, even thought it's getting about 5.15. If you want to use true AFR, most wideband meters can be set to show the correct AFR for the fuel, but the lambda will show the same. If you have an application that uses part throttle, don't be afraid to run lambda 1 at part throttle - it's fine.

2) Methanol has a pre-ignition sensitivity of LESS THAN 0! This means it doesn't take much of a hot spot to nearly instantly destroy your plugs/pistons/exhaust valves. This means you need colder plugs, and should run a shade rich at the beginning of the program. If the cold plugs are running fine, there's no benefit to trying hotter plugs, so don't do it unless you've got a very very good reason to do it.

3) Don't immediately assume it needs more spark advance than gasoline. It'll be able to tolerate it, because it's very unlikely to knock, but, it might not be making any more power, while also bringing you closer to pre-ignition destruction.

4) The EGT will be lower. But, it'll show the same trends as gasoline, and you're right about it being able to get a hot exhaust when it's so rich that it's burning slowly. If I were doing this in a racing or dyno program, I'd have 8 EGT's and 2 widebands, no less, unless you like wasting a lot of time and hair. Forget about reading them damn plugs for AFR, except DO go looking for signs of porcelain bubbling or actual bits of aluminum sticking to the electrodes!

5) Don't play with methanol - it'll make you crazy and blind, or burn you. The exhaust contains formaldehyde (and methanol), and more so when rich - so don't run it indoors.
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Re: Methanol Plug Reading

Postby induction apprentice » Sun Sep 09, 2012 1:16 pm

If your cylinder head has room for a 13/16ths plug body and 3/4 " reach? You could go with the NGK alcohol plug ( 6061-9 ) will work pretty good for you and has the correct cad.
They go by stocking numbers now. Not part numbers. So you might have to get the counter guy to cross it or google it to get the stocking number.

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