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Master Chief · 06-17-2008, 03:43 PM

Here you go : 3/8NPT to 10AN -
http://www.anplumbing.com/shop/index...&dept=Aluminum

Part number - 981611

Mine is a Black Top VVT, but this should work for you as well.

The hole in the cover is 16mm, but at its end, it shrinks to about 11mm.

I used a 15.5mm drill bit to drill the hole in the valve cover all the way thru.

If you dont use a drill to enlarge the hole all the way thru, you wont be able to run the TAP deep enough to get a good tread for the adapter.

I used 15.5mm, as i didnt want to risk enlarging the hole more the 16mm.
I then used a 3/8 NPT tap, wich wen in very smoothly to tap the hole.

Another thing is that most 3/8NPT to 10AN adapters, have an ID of about 10mm on the NPT half, and and ID of about 12mm on the AN half.
I used a 12mm drill to go thru the adapter to make it all the way 12mm ID.
You dont have to do this, but as i was already on it, i thought i would make all the passages as big as possible.

Here you can see how it looks on the Rear of my Valve cover. The same goes for the middle of the cover.

BTW Catch cans, wich one do you have ?
Some of the catch cans, like GREDDY's and other Jap makers, dont hae 3/8" NPT, but have 3/8" BSPT ports !
Basicly the difference is in the number of threads per inch - its offset by 1 thread.

I have the Greddy one and what i did is simply run the 3/8" NPT tap, thru the Catch can port treads, and it works fine with the above 3/8"-10AN adapter.

Remeber to clean all those tapping and drilling chips, after the act - before you install anything.

Good luck !

06-17-2008, 03:43 PM	#13
Master Chief Zilvia Junkie Join Date: Feb 2006 Location: Israel Posts: 332 Trader Rating: (3)	Here you go : 3/8NPT to 10AN - http://www.anplumbing.com/shop/index...&dept=Aluminum Part number - 981611 Mine is a Black Top VVT, but this should work for you as well. The hole in the cover is 16mm, but at its end, it shrinks to about 11mm. I used a 15.5mm drill bit to drill the hole in the valve cover all the way thru. If you dont use a drill to enlarge the hole all the way thru, you wont be able to run the TAP deep enough to get a good tread for the adapter. I used 15.5mm, as i didnt want to risk enlarging the hole more the 16mm. I then used a 3/8 NPT tap, wich wen in very smoothly to tap the hole. Another thing is that most 3/8NPT to 10AN adapters, have an ID of about 10mm on the NPT half, and and ID of about 12mm on the AN half. I used a 12mm drill to go thru the adapter to make it all the way 12mm ID. You dont have to do this, but as i was already on it, i thought i would make all the passages as big as possible. Here you can see how it looks on the Rear of my Valve cover. The same goes for the middle of the cover. BTW Catch cans, wich one do you have ? Some of the catch cans, like GREDDY's and other Jap makers, dont hae 3/8" NPT, but have 3/8" BSPT ports ! Basicly the difference is in the number of threads per inch - its offset by 1 thread. I have the Greddy one and what i did is simply run the 3/8" NPT tap, thru the Catch can port treads, and it works fine with the above 3/8"-10AN adapter. Remeber to clean all those tapping and drilling chips, after the act - before you install anything. Good luck ! Last edited by Master Chief; 06-17-2008 at 04:04 PM..