I keep reading conflicting things with spark plugs gap. I hear some say stock gap (.044) is fine for FI applications while low boost (under 10). While others say to decrease spark plug gap to .028.

Also, does take pics of their plug tips after removing them? I have 4 that I just removed that look very similar, while two look slightly different.

 

checking plug tips only works if you shut the engine off immediately after a run. I mean IMMEDIATELY!!!...............like as soon as yuo cross the 1/4 mile finish line. then you just coast the car back to the pits to analyze the plugs.

 

gotcha...I guess the same would apply on the dyno.

 

Engineers sample the secondary voltage and look at the waveform with different plug gaps under highest load to arrive at a starting gap so that at 60k-100k things still function from wear down. Since WOT acceleration requires the highest voltage [~~22-25KV depending on electrode diameter] important to look at voltage under these conditions.
http://www.picotech.com/auto/wavefor..._ignition.html

Labs use a pressure sensor that looks like a metal washer with a wire attached to measure peak pressures as the spark plug stretches minutely.

http://www.optrand.com/PSIplug.htm
http://www.ngksparkplugs.com/techinf...stallation.asp