I finally got around to getting an aem FPR. It said the drilled and tapped holes were 9/16 x 18. I always thought they were NPT, pipe thread, but it didn't look like it.

I wanted to use all factory sized lines, no special fittings or anything. I checked the factory hose, and the hose I have fitting snug is a 5/16" which comes out to 7.9mm. I saw AEM sells a 7mm barb fitting, I don't want to buy it and it ends up too small. Anyone else have this fpr that can give me a quick enlightening?

 

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