Subaru WRX Forum banner

1 - 10 of 10 Posts

·
Registered
Joined
·
81 Posts
Discussion Starter #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.
 

·
Registered
Joined
·
905 Posts
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).
 

·
Registered
Joined
·
1,344 Posts
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
 

·
Registered
Joined
·
3,235 Posts
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.
 

·
Registered
Joined
·
81 Posts
Discussion Starter #8
Holy crap my old ones were fouled! Reddish orange high heat glazed. It probably happened when I tried a chepo CAI in it.
 

·
Registered
Joined
·
2 Posts
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.
Dielectric grease does not conduct electricity. It is used to insulate and seal out moisture. Still good to use. But it doesn't directly create a better circuit.

Jeff
 
1 - 10 of 10 Posts
Top