What Does This Spark Plug Comparison Tell You. (Used vs. New) NGK TR6’s

[GM2Ford]

Here’s a little history to the used spark plug removed today. I’ll make a long story short.

Upon 1st start up of the new short block... about 5 months ago, I’ve been slowly but surely trying to remote tune this car and fighting some extremely rich & extremely lean issues. Never really even got to properly break anything in because of major drivability/neutralilty ->(made up word to describe engine running bad in neutral lol) issues.

Used Spark Plug “Use” During Engine:
1. Probably cranked and started this thing over 500 times within those 5 months while trying to figure stuff out.
2. Drove less than 300 miles.
3. Engine run time in neutral is probably worth about 3 full tanks of E85.

Done. Here’s a picture.

Onto SVTP communities thoughts on this!

Thanks

 

[SVT_Troy]

What cams are you running and who/how was the timing set? If stock cams did you put the correct cams in the correct position?


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[MG0h3]

Plug looks fine to me but some more shots would tell more. I dont see oil, fuel fouling, or anything really.

Light yellow or tan is how the ceramic should look.

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[01yellercobra]

I have to agree with MGoh3. It doesn't look bad. However, is it me or does the porcelain look like it's not straight?

 

[04OWwhipple]

I have to agree with MGoh3. It doesn't look bad. However, is it me or does the porcelain look like it's not straight?

I noticed this and that the porcelain on the new plug is much taller in this picture it seems


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[BlckBox04]

I have to agree with MGoh3. It doesn't look bad. However, is it me or does the porcelain look like it's not straight?

I think it's the picture angle, that looks fine really, just maybe a little too rich which is why it's all black

 

[SVT_Troy]

I think it's the picture angle, that looks fine really, just maybe a little too rich which is why it's all black

I agree it’s the angle the new plug is being held at. Look at the electrode. It’s the same length as the new one so I don’t think it’s worn down. The porcelain being a different length would be a different type of plug not worn.

OP does your car idle at all or runs really rough? I’m trying to get a feel for how bad it’s running? Not being able to tune it could be a few things outside of extreme tuner error. Cams being swapped, timing far off, 02 sensors swapped, ECU bad are the main things I can think about.

I have my intake/exhaust cams swapped and it ran like crap, the one bank was super rich and couldn’t be tuned but would run.


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[GM2Ford]

I think it's the picture angle, that looks fine really, just maybe a little too rich which is why it's all black

Yeah it was running extremely rich for a long time.

I agree it’s the angle the new plug is being held at. Look at the electrode. It’s the same length as the new one so I don’t think it’s worn down. The porcelain being a different length would be a different type of plug not worn.

OP does your car idle at all or runs really rough? I’m trying to get a feel for how bad it’s running? Not being able to tune it could be a few things outside of extreme tuner error. Cams being swapped, timing far off, 02 sensors swapped, ECU bad are the main things I can think about.

I have my intake/exhaust cams swapped and it ran like crap, the one bank was super rich and couldn’t be tuned but would run.


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I haven’t changed ecu. I am still running my factory 1999 GT ecu with is coded “GTG1.” I bought a GTG3 just incase I learn that my original one is bad.

The heads are stock low mile 03 Cobra heads w/ factory 03 Cobra cams and hardware on the heads. I had the heads gone through & freshened up at the machine shop and checked before they went on the engine.

Right now it idles good. A few days ago I tried to start it up in 18 degree weather and it was giving me major issues. I’m on an E85 base tune.

To answer your tuning/drivability concern:
During the very first few base tunes, it was running super rich and extremely rough. Which ended up damaging my wideband o2 sensor. So after a break from the car, I’m just now replacing the wo2 sensor and replaced the upstream o2 sensors with OEM ones too. When I would drive the car around the block, it would sometimes feel very stumbling or shaky under anything slightly above just easing into it slowly. However, if I stabbed the throttle 3/4’s for a quick second, the power felt good. But for it to drive smooth, I’d have to grandma the thing around lol. I don’t have much seat time since though.

Anyway,
While I was replacing the o2’s, I decided to replace the spark plugs and check them just incase. So that’s where this thread and picture came from.

Here’s some more pictures of the plugs for inspection. Plugs on the right are passenger side from front of the engine to back. Plugs on the left are driver side from front of engine to back. (Assuming images are read from left to right)

 

[gt347mustang]

I didn't read the whole thread, but it sounds like your tune sucks or something is majorly wrong causing the car to run poorly. What does your tuner have to say?

 

[Shadow Grey 03]

18 degree weather and e85 cold starts aren't friends. There is a reason they go to e70 in the winter. If it is rich on start up to go with the temps, then that would make it difficult to start.

 

[03' White Snake]

Just an FYI, my car starts and idles very rough on cold days on E85. It pops and backfires in the exhaust. Can barely back it out of the garage to let it warm up before driving it. After it warms up it is fine.

What gap are you running? How much Boost? Check your boost bypass is actually working, mine idles like crap if this is not working. Should be open during idle and close under light throttle. Possible vacuum leak? How much vacuum you pulling at idle?

You want the largest gap possible without spark blow out. I'm running 22 psi and my plugs are gapped at 0.028". I've heard people running down to 0.022" with high boost.

 

[BlckBox04]

I could just be the lighting but now they look orange which is lean

 

[Avispa]

Those plugs look clean. Too rich leaves "fluffy" black deposits on the ground electrode and on the threads. Don't see anything that looks fluffy on any of your pics.

 

[GM2Ford]

I didn't read the whole thread, but it sounds like your tune sucks or something is majorly wrong causing the car to run poorly. What does your tuner have to say?

It ran poorly in the beginning. It runs okay now, still on just base tune. I was just wanting a second opinion on the plugs since they were in the engine when the tune wasn’t finalized.

Just an FYI, my car starts and idles very rough on cold days on E85. It pops and backfires in the exhaust. Can barely back it out of the garage to let it warm up before driving it. After it warms up it is fine.

What gap are you running? How much Boost? Check your boost bypass is actually working, mine idles like crap if this is not working. Should be open during idle and close under light throttle. Possible vacuum leak? How much vacuum you pulling at idle?

You want the largest gap possible without spark blow out. I'm running 22 psi and my plugs are gapped at 0.028". I've heard people running down to 0.022" with high boost.

I changed the new spark plugs to just below 0.027. The old ones where at 0.028 gap. So I thought that’s why it wouldn’t start in the cold weather.

For boost,I’m at stock 3.5” 2.9 Whipple pulley. Not sure how much boost that is, 17lbs? I also have a 3.0” pulley which should be 22lbs? Stock lower for now.

Those plugs look clean. Too rich leaves "fluffy" black deposits on the ground electrode and on the threads. Don't see anything that looks fluffy on any of your pics.

Yeah I just wanted to know if anyone thought the used plugs had signs of abnormalities.

But sounds like they are good. So I’m not worried.