OE Spark Plug Gap Range
 

The workshop manual reads 0.043 (standard) to 0.055 (max.).

In a non boosted application using OE or OE equivalent plugs; has anyone had positive results opening the gap more toward 0.055?

I like to hear from those with both negative and positive experiences and what your gap numbers are/were.

Thanks for your insight! :tiphat:

PS- The only info. I could find in search related to boosted applications.

I run the GTR plug at .031” on 93 gas and E85.

I know thats a tight gap, and it has worked well for me.

Natural of course.

From what I've read. The higher the pressure, the smaller the gap. If your N/A open them up to get the biggest spark. If your boosted or running some sort of high comp engine or nitrous you need a smaller gap so the spark can make it across.

I personally opened all mine up (can't remember the exact #) made sure they were all the same. And I also got a index washer kit so that they were all pointing towards the intake side.

I can't really say there's more power but the engine sounds smoother to me.

I found the existing OE Plugs to be at a smaller gap than the manual recommends 0.038". I opened the new units to 0.041", the lowest of the scale the manual recommends.