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mopsi
07-13-2005, 11:18 AM
Is there a link or local guru that knows gapping? The OEM specs are for 11lbs of boost at sea level. Since we are at 5280' and 20-30lbs of boost, what is the ideal gap? I plan on getting the plug coils on EBAY for $300 in a few weeks. BTW this is for a 4G63 engine w/ stock coils and wires. I am pushing around 500hp w/ NOS.
sbiggi
07-13-2005, 02:10 PM
You want to run the biggest gap you can so you get a bigger spark.
Gap the plug down till you dont get blowout.... that how you know.

Stock is .028-.026
I have to run mine at .024 otherwise the spark blows out, but I have 12 year old coils which need to be replaced.
mopsi
07-13-2005, 05:30 PM
You want to run the biggest gap you can so you get a bigger spark.
Gap the plug down till you dont get blowout.... that how you know.

Stock is .028-.026
I have to run mine at .024 otherwise the spark blows out, but I have 12 year old coils which need to be replaced.

I gapped mine at .035!!! No wonder it falls off at high boost. Thanks for the info!
DSMRacer657
12-08-2005, 11:40 AM
Well whenever I do a DSM it has a MSD replacement coil, ngk wires, and ngk v-power copper core cold plug gapped at .030 has worked great for 30 psi
sbiggi
12-15-2005, 09:09 AM
Well whenever I do a DSM it has a MSD replacement coil, ngk wires, and ngk v-power copper core cold plug gapped at .030 has worked great for 30 psi

I used my brother's COP and was able to run .028 with no problem.

I then swapped my original 90 coils back in and I get blow out when its cold out at 23-25psi. I think mine would be fine with .027 or so. My butt dyno didnt notice any difference in power with the larger gap, and my gas milage didnt change either.

-Seth