1972 California 318 EGR

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vames

vames

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Hi All. It's come to my attention that my 1972 Swinger w/318 probably had some add-on emissions devices because it was sold in California. The first was the NOX system, which was long since disabled and I've now completely removed.

But the second was an always-open EGR. There is no vacuum valve on my intake manifold and I want to take a look and see if there are indeed open jets down there. The FSM for the year mentions that California cars had this, but it doesn't show any pictures or diagrams. Can someone describe what I'd be looking for? Do I have to remove the carb or can I just see them through the carb? If they are down there, is there a way to plug them?
 
They are a weird looking jet/plug under carb in intake.
I plug them for racing. Beware they are an unusual thread
that I can never find anywhere so I tap them to a regular
plug that I can find. I do not suggest tapping then with
the manifold still on heads.
 
There was a flat plate that fit over the EGR base (bolts to the intake manifold boss where the EGR would be). Not sure if this is all you need to delete the system.
 
Thanks. Can they be taken out then tapped themselves to take a plug, then threaded back into their holes?
 
If your intake has NO place to mount the EGR, but Does have working floor jets, that would be a continuous EGR set-up.
If your intake has a place to mount an EGR, then the valve is used to proportionally regulate the amount of EGR.
Properly working, in stock configuration, EGR is never a problem. Well except on PT fuel-economy.
If your intake has the floor jets, they should be visible right under the carb, at WOT. If they are threaded they are NOT Pipe-thread, as already stated.

If you have the continuous-feed jets, and headers, and a non-stock cam with significant overlap; then the jets need to be plugged, or better yet, defeated at the intake to head interface. If you have the EGR-pad, simply bolting on a plate, or disconnecting the plumbing to the valve, defeats it. However, the valve can leak, whereas the plate cannot.. If you block the ports at the heads, then the open jets do nothing, except perhaps cause turbulence; but on a 2bbl street-engine, I sure wouldn't worry about it. I have seen them brazed shut, and the standpipes removed.
If you do NOT have headers, and do NOT have idle-issues, I would just leave it be; in all likelyhood, the passages have been carboned up for decades.
 
Steven Vames said:
Thanks. Can they be taken out then tapped themselves to take a plug, then threaded back into their holes?
Click to expand...
I don't think so. From memory those jets are removed with a square-drive extension , so the jets are square drive. If you take them out, and flip them over, I suppose you could braze a little flat plate on there, and then re-install them. I think I have seen that done one time; but I think they are SSsteel..
 
Why not use parts from a federal emissions vehicle that does not have all that stuff?
 
Syleng1 said:
Why not use parts from a federal emissions vehicle that does not have all that stuff?
Click to expand...
That is certainly an option. But I’m trying to get by without buying, painting and installing a new old intake manifold. Honestly there are no big telltale signs (maybe a tiny bit of idle roughness but not much) that I have open EGR at idle. But if there is a simple way to reverse what seemed to be a hasty and poorly conceived decision that Dodge made back then, I’d like to do it for the sake of fiddling.
 
I have the stainless factory plugs which I want to keep. I also have a pair of stainless bolts to shorten and install to plug. PM me. They may be carbon plugged already.
 
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