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Plug Gap?

86K views 10 replies 6 participants last post by  Tevin 
#1 ·
Does anybody know the spark plug gap on a 05 EJ20 WRX? I cannot find that info anywhere on a sun afternoon. Just bought some NGK Iridium IX plugs and the auto parts store people said they were pre=gapped....wrong. 2 were .030 and 2 were .040. same part no.
 
#2 ·
Gap has a lot to do with igniteability. The bigger the gap, the better combustion. HOWEVER, this comes at a cost. The bigger gap requires MORE voltage to spark, putting a much higher strain on your ignition system. With a turbo charged motor, the gap is usually smaller. This is due to the fact that higher cylinder pressures make it harder for the plug to fire, therefore increasing voltage requirements (this is why 2.5L NA is 0.044" gap and the 2.0L and the 2.5L turbo is 0.028 to 0.031" gap).
 
#5 ·
Gap has a lot to do with igniteability. The bigger the gap, the better combustion. HOWEVER, this comes at a cost. The bigger gap requires MORE voltage to spark, putting a much higher strain on your ignition system. With a turbo charged motor, the gap is usually smaller. This is due to the fact that higher cylinder pressures make it harder for the plug to fire, therefore increasing voltage requirements
That is why the WRX has coil-on-plug ignition !Thumbs Up
 
#7 ·
I gapped my Pulstar plugs to 0.030, applied some anti-sieze to the threads, and a smeared a small glob of dielectric grease on the ends to ensure a good electrical connection. Good to go for another 30,000 miles hopefully. Also, don't torque them down too tight - just snug em gently.
 
#11 ·
Does anybody know the spark plug gap on a 05 EJ20 WRX? I cannot find that info anywhere on a sun afternoon. Just bought some NGK Iridium IX plugs and the auto parts store people said they were pre=gapped....wrong. 2 were .030 and 2 were .040. same part no
Bro literally same shiit my car started missfiring and then I gapped all of them at 28 but I am getting missfires in cylinder 1,2,3
 
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