Thread: Spark plug gap

To keep this easy for search purposes in the future. What is the best spark plug gap to use with our cars for:


1. Factory ignition
* Naturally aspirated
* Forced induction

2. Aftermarket ignition
* Naturally aspirated
* Forced induction

I think i should have posted this thread in general sr20 because it applies to turbo and all motor. If anyone feels they need to move it feel free.

thats a tough question as gap has alot to do with the spark plug, the ignition system and the coil system, spark plugs, i guess there could be a general gap for the above listings but its really going to come down to each and every individual setup as some people may have a better ignition setup that allows them to have more spark and some might not which would mean one engine could have a larger gap and the other a smaller

there is one rule to spark plug gap!

run the largest gap you can without blowout. that is all. turbo, nos, NA, doesnt matter. you will get the most power, and best fuel economy when you run the widest gap.

also try sidegaping and indexing them for maximum output.

X2. Couldn't have said it better.

You mentioned spark plug blow out, What is that? How can I tell if it's happening to me if I can't see into the cylinders?

Wats the recommended gal on iridium plugs ngk?or does it matter.don't mean no offense to your post sir

when you start to accellerate and the car starts bucking or missing that is when you know your spark is being blown out from too large of a gap