The Smog port? I'm pluging the injection port. Does it line up with the valve?
I could not find 10 X 1.0mm 45 mm long socket head cap screws, so I cut the heads off of some regular cap screws and RTV sealed them. the 17mm head interfered with the intake manifold. Should of just ground the cap round and cut a screw slot.
Thanks

RTV? I doubt that will hold. There is fire under them if you did what I think you did.
Www.mcmastercarr.com. Try looking there. Or google Metric Hardware and see if you can find them that way. Don't use RTV and introduce a big leak.

Zach

Thanks Zack.
Did not like the way I installed the plugs.
I did check McMaster Car and Grainger, no 10X1.0mm X 47 long Socket head cap screws. For that matter 10X1.0mm seems to be kind of an oddball size.
I have a a Fastenal Store near me. They don't list The socket head Cap screws. Back to Grinding the 17mm heads down to clear the intake runner flange.
Glen

Why soooooooo long 45mm??? Mine looked like regular short allens, when I rebuilt one car. I guess the PO had installed them at rebuild with a long hex. On my other car I left the nipples in the head and put 3/8"npt caps on them.

The ones on my old '75 heads were Allen set-screws, 3/4 " or 1" long at the max.

I have no idea where they came from (a PO installed them), but I'd think any good hardware store with a decent 'Bolt Room' would carry them.

Are there pictures of the exhaust port that show the injection point. What I don't want to do is run a screw into a valve.
Thanks

1-Are your heads still on the car?
2-Do you still have the nipples?
3-What do you mean by injection point because I don't want to say "right in front of the intake valve".

I try to make mods that are easily reversible, so here is what I did.
Tom

You won't hit a valve. If you have the old injection pipe, look at the length of the thread and match that depth as the pipe bottoms when it runs out of thread. The pipe is only threaded less than an inch as I remember. And the hole is in the exhaust port ............

A 3/8" NPT pipe cap may look funky, but it works very nice. I did mine that way and it went 5K before I sold the car. I did have one loosen and come off ... makes a hell of a racket

oh - i see.

OK I just wanted to keep that area clear. The caps look OK
Glen

I had the Allen 'plug' at cyl #1 come out once. I didn't realize it was the Allen at first, I thought I just had an exhaust leak. (which it actually is, being that it's an air-injection port bore going down into into the exhaust port just beyond the valve).

At first, I removed the muffler and left HE and replaced the copper exhaust seals, but still had the leak

Next, I checked it at night and saw flames shooting out of the port. I looked around and found the Allen laying on the engine shelf. I removed all of the plugs and added a small dab of blue lok-tite when I reinstalled them.

Ok too much thinking. #1 cylinder port threads were stripped. Got the calipers out and found that 1/8" allen head pipe plugs were slightly larger in diameter, and the threads were close to the same pitch, so installed them. Problem solved.

RTV will not hold.

Try this. Cut the injection lines about an inch out and pinch them shut. Then braze them to seal them.

Or, pull the heads and have them welded up.

10mm valve adjuster screws will work.
I just left the smog tube heads on, so I'd have something to wrench upon and MIG welded the tubes shut.