How to read spark plugs? Rich or Lean?
 

I know the spark plugs never lie in terms of tunning; but how do I read them, meaning what do the colors mean? How can I tell if I'm running rich or lean? Do I look at the electrode tip or do look at the white part below?

Thanks.

Re:How to read spark plugs? Rich or Lean?
 

I believe in the haynes repair manual they have a section that shows a pic of each condition(detonation,oil cons, etc.) and explains possible causes and solutions to them.

Re:How to read spark plugs? Rich or Lean?
 

Yeah, but their pictures are extreme situations. I have never seen sparkplugs damaged the way they show them.

Re:How to read spark plugs? Rich or Lean?
 

Ya, that's true. I don't know what to tell ya then.

Re:How to read spark plugs? Rich or Lean?
 

theres tons of sites out there with info just search, in your other post you said the plugs were grey.. that is normal not lean.
http://www.ngksparkplugs.com/techinf...q/faqread2.asp

Re:How to read spark plugs? Rich or Lean?
 

rich the plugs will be black lean they will be whitish kinda tan is the ideal color

Beau

Re:How to read spark plugs? Rich or Lean?
 

Thanks for the website bro. I am going to try bigger injectors and turn the fuel pressure down, gap the plugs around 28. It will probably run rich at idle but I should have enough fuel above 3500rpms. I just think the MSD's spark is alot hotter than factory and that the stock injectors can't flow enough to keep up with hotter spark.

I will keep you guys posted. Thanks.

Re:How to read spark plugs? Rich or Lean?
 

Saw your other post on your lean problem. A hotter spark has no bearing on fuel consumption/needs. IMHO

Whats your complete setup?

Re:How to read spark plugs? Rich or Lean?
 

8AN stainless fuel line from tank to motor
AEM high volume fuel pump
Aeromotive fuel pressure regulator
Bosch 405 lph fuel pump
Aeromotive fuel filter
450cc Mitsu injectors
MSD 6AL with Blaster 2 coil

I put the 450cc injectors in and now it is too rich. But my Air Fuel ratio gauge still reads lean. I know I am running rich now becsause the plugs are fully black.

I am putting my turbo kit on today and after I get it tuned I'll let you know how it turns out.

Thanks.