I was always taught that if a plug is white after a run you are lean and if it is dark you are rich.. Now I hear that with TR6's they are always white after a run.. I need some input..

 

Yes, they run slightly white, the best thing to look for is if the gap has changed a lot, and pitting, these would be good indicators that you were running lean.

 

I pulled out one of my TR6's and it was green, I'm sure that isn't good, don't know exactly what that is...

 

A lot of time gas treatments, octane boosters, etc. will cause plugs to turn funny colors.

 

Here are some good rules of thumb:

-Read fuel mixture on the base circle of the plug (flat part of round ring)
-Read heat range on the electrode (should see a color change about half way up if range is correct)
-For detonation, look for pitting on the electrode and/or ceramic portion--also could be soem shiny metallic particles if the detonation is severe (aluminum), or missing electrode
-If using N2O, you must shut the car down immediately at the end of the track to read the plugs--best to do this for any application, because part throttle return to the pits can change the readings

 

Thanks guys.. So pulling the plugs out after a 3 second nitrous run is not correct and will not give me a accurate reading. Plus, it is a 5 to 8 minute ride back to my stopping point and another 15 minutes for the plugs to cool long enough for me to get them.. My car normally runs lean on motor anyway at part throttle..

 

Most people that I know check plugs on the dyno when tuning.

At the track they pull them and look for pure detonation...not really reading them, just making sure that they are ok.