[535_BiTurbo]

A few months ago, I found out my spark plugs in my 550i stg 1 jb were gapped at .042, which made my top end and mid range weak. I gapped them down to .028 and it pulls like a freight train.

Should I gap my plugs down even more to .020? or just stay at .028?

My buddy has a '15 Subbie WRX (not STI) manual with muffler delete, fuel pump/flex fuel lines for E85, top mount intercooler, down pipe, egr/tgv delete and BrenTuning/Cobb Pro tune, supposedly makes 330-350whp and he wants to run me and claims he can beat me. I was going to gap my plugs down even more and run a Torco/NOS booster mix to 93.

[EL Jeffe 5]

if car is running fine I personally wouldn't do it

[535_BiTurbo]

Yea its running fine, I was just curious if it would run better with a tighter gap

[MissionPerformance]

If you are running any sort of tune, flash or box, its very advisable to lower the gap on the plugs. Stock ignition on N63 and S63 is relatively weak and lowering the gap helps the coils provide a usable spark. We found that a good gap for stage 1 flashes is about .022 and .018 for stage 2

[535_BiTurbo]

awesome! I will be doing plugs this weekend and gapping them at .022

[Dietani83]

Hi I have a 550i step2 colder spark plug.020 inches? Or mm?

[MOBF10]

Originally Posted by Dietani83

Hi I have a 550i step2 colder spark plug.020 inches? Or mm?

[badblack550xi]

Originally Posted by Dietani83

Hi I have a 550i step2 colder spark plug.020 inches? Or mm?

inches

[warpeacelove]

Originally Posted by MOBF10