any one that has converted to an fittings know which swagelok fitting was used on the oem hardline coming out of the firewall
thanks

 

I'm pretty sure it's in this thread
https://honda-tech.com/zerothread/1527379
Though I didn't want to read through 20 some pages to find it for you. That'd be a place to start. I see you've already posted in there but they may be reluctant to answer seeing as how it's all been posted.
Or pm ef8kid. I don't know him but he seems like he's pretty willing to help out.

 

either one of these will work:

http://www.swagelok.com/search...0-7-4

http://www.swagelok.com/search...0-7-4

this is the difference between the two:

8mm=.3150 inches

5/16=.3125 inches


the 5/16 fitting actually fits more snug to the pipe.

Then u just need this hose end:

http://store.summitracing.com/...w=sku