i recently got a retune, old tune had a fair amount of knock. just got the thought that maybe i need plugs that are a step colder. so, i took a pic of the plugs, looked up this site: http://www.4secondsflat.com/plug_chart.html and came to the conclusion that my plugs look like picture #23.

so,
1. i could use a couple of second opinions on what picture my plugs most closely resemble.
2. from past research, i thought that stock plugs would be the best choice for a 9 with just an exhaust and tune. but this chart (apparently it's from NGK) suggests going with a colder plug. any thoughts/ recommendations?

 

Can you take a closeup pic of the insulator/electrode area please? Any idea which plug came out of which combustion chamber(1-4)?

 

ok, broke out the D70 for this.
the plugs are arranged as they came out of the motor. left most plug = left most cyl, and so forth.

 

You're def shifting to third too early.
















seriously, its hard to read plugs through pictures.

Scorke

 

 

The reason that I asked for a close up is because at my age I can't see sh*t, and I wasn't sure but was looking for any signs of detonation. Specifically, are there any itty-bitty specs of aluminum visible on the insulator nose?

I'd say that things look a tad lean and EGT's are getting up there a bit. Is your car tuned? And what sort of gasoline are you running on and at what boost level?

 

http://www.strappe.com/plugs.html
http://www.dragstuff.com/techarticle...-pictures.html

2nd link is pictures and links at the bottom, top link is a good read, wish everyone would read it.

 

What kind of driving were you doing before pulling the plugs? Just wondering because I think an accurate representation requires going WOT and cutting the engine at the end of the run.

 

I'd agree with the previous poster, assuming your tuned and you were giving it full stick before you shut off I'd say your looking pretty good, if anything a TEEEENY bit lean.

It's cheaper to buy a wideband I'd say

Scorke

 

I agree with this.

The best way that I have found to read plugs is after a tune is completed, put a fresh set in. Fire the car, warm up, 3rd gear pull, cut engine, pull plugs and read.

Those plugs do not look bad from the pictures, especially if they have a good amount of miles on them and the car had recently been beat on. Maybe a little lean. Good luck.

 

Those plugs look just like mine, and i have a REALLY conservative tune. A/F's in the upper 10's.