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Discussion Starter #1 (Edited)
I know what I think but I want to hear other opinions.









These are not after a quarter mile pass or anything like that. These are from a normal drive on the freeway for about 30 minutes, get off the freeway, and drive about 1/2 mile off the freeway to my house in stop and go traffic.

I have about 3 months on these plugs.

What do y'all think?
 

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Getting a picture further down is better for reading a plug. Maybe slightly rich at cruise if that's all the driving you have on them. I'm sure there's a ton more opinions probably from more experienced guys too. Are you running an out of the box carb? Fuel distribution will also be different depending on manifold and exhaust etc... Standard holley and dual plane manifold? maybe drop two sizes and see how it runs.
 

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Discussion Starter #4
Getting a picture further down is better for reading a plug. Maybe slightly rich at cruise if that's all the driving you have on them. I'm sure there's a ton more opinions probably from more experienced guys too. Are you running an out of the box carb? Fuel distribution will also be different depending on manifold and exhaust etc... Standard holley and dual plane manifold? maybe drop two sizes and see how it runs.
What do you mean further down? Got my camera right here. 750DP, stock jets, haven't touched them yet, single plane, correct PV.

i would try and smell the plug also. can you smell fuel?
There slightly wet. I could not smell anything. I use a anti seize lub on he threads, but slightly wet.
 

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Yeah its tough to get a good picture because of the shadow created by side lighting. The area deep into the plug is better for reading the burn color. Gray-tan is about as good as you can tune without O2 and a good wideband a/f. Your plugs look to be a bit dark but not overly bad. It may also be the distribution from running a single plane on the street. Vacuum signal is poor usually at idle and low speed causing a rich condition. Also if your running a single plane that usually means a big cam too which also contributes to poor mixture at lower speeds. So driving around town and on the freeway then reading the plugs might not be the best way to evaluate your combination. It's a tough one. Your engine may be running great and the tune could be awesome for power but the quick drive around the block or return home at slow speed could be soaking the plugs. It's better to read them after a wot run then shut down with minimal low speed running to really get a good read.
 

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Discussion Starter #6
I agree with everything your saying. I am just looking for somebody to say, timing mark on ground strap is ok, I know its hard to see, but in the 4th pic down is easy to see to me or say jets on the baseline is ok, or what you said, might be a little rich try jetting down.

I just want people to comment on the plug regardless of what engine combo, etc.
 

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without seeing it in pesron .... it does look a little rich . brob for the low speed driving around. if your running a single plane intake , i would drop the front jet size down 2 #'s from what ever it is now . that will keep it "clean" under part throttle driving around stop and go conditions . be sure you have the right power valve in it for your app. if your not sure how to do that i'll be glad to explain it but thats for another long post . lol hope that helps
 

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Like Pandora said it looks a tad fat. What dizzy are you running? RICK
 

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Yeah its tough to get a good picture because of the shadow created by side lighting. The area deep into the plug is better for reading the burn color. Gray-tan is about as good as you can tune without O2 and a good wideband a/f. Your plugs look to be a bit dark but not overly bad. It may also be the distribution from running a single plane on the street. Vacuum signal is poor usually at idle and low speed causing a rich condition. Also if your running a single plane that usually means a big cam too which also contributes to poor mixture at lower speeds. So driving around town and on the freeway then reading the plugs might not be the best way to evaluate your combination. It's a tough one. Your engine may be running great and the tune could be awesome for power but the quick drive around the block or return home at slow speed could be soaking the plugs. It's better to read them after a wot run then shut down with minimal low speed running to really get a good read.
I agree.

Something like this is better to be seen in person, since lighting and details aren't as good with pictures like that. But personally I don't see anything so bad that I would feel the need to start retuning the combo, unless there was some sort of noticeable driveability issue as well. The plugs don't look bad for some stop-and-go street driving in a carbed application. Only way you'd ever get a perfect A/F ratio would be to tune with a wideband, and even then a carb is not going to maintain as precise of a ratio under every possibile driving and weather condition that EFI would.
 

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Discussion Starter #14
Are you burning any oil?
Not burning any oil. Oil level looks perfect,/

Like Pandora said it looks a tad fat. What dizzy are you running? RICK
I'm running a MSD pro billet.

Some nice toilet material for you about reading plugs.

http://www.dragstuff.com/techarticles/reading-spark-plugs.html
Yeah I've read this before and other stuff from there website. Really good stuff.

The reason I ask the question what do you think of the plugs is because just the other day the car became hard to start. I looked at the plugs and they looked like they are starting to get fouled causing a hard start.

I since changed the plugs, and dropped the primary jets 2 from 71 to 69.

I have yet to take the car for a drive, as I need to check the float level, and set the idle mixture screws.
 
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