Smog Port Plug Size

[TNfiat]

Does anyone know what size plugs I will need to buy to plug the smog ports shown in the pic below? I have a 78 Fiat Spider 1800 stock engine.

Thanks in advance for the help

[BwBrown]

One of the vendors on this site sells a set of four plugs for this purpose at a very reasonable price.
Can't remember which one, but I bought a set - and they fit.
Maybe they will weigh in.

[So Cal Mark]

12x1.25

[klweimer]

Pretty sure Autoricambi sells the set.

[TNfiat]

BwBrown: thanks for the suggestion. I would like to support the members on this forum by purchasing from them so hopefully someone suggests a name that I can contact to get these plugs ordered.

Mark: thanks for your prompt reply with the sizes. That's a big help to locate some.

klweimer: thanks - are they part of this forum? I'm new here - see my intro that I posted yesterday.

thanks again everyone,
norm

[AriK]

Yes Norm, if you can't find them locally, i also suggest Auto Ricambi. Both Vandor and Ramzi are members here. They're not just counter people, they're true connoisseurs of the brand.

[klweimer]

Hi Norm,

A few useful parts suppliers:

Autoricambi- http://www.autoricambi.us
Allison's Automotive - http://www.allisonsautomotive.com
Vick Autosport - http://www.vickauto.com
Midwest-Bayless - http://www.midwest-bayless.com

Autoricambi is my go to group for all the stock bits you need, as well as some performance pieces. Csaba and Ramzi are on this site a lot and very knowledgeable.

Allison's is all about performance and has good stuff too. Mark Allison is the forum moderator. Also very knowledgeable. I have a variety of performance items from Mark on my car.

People on the forum run hot and cold on Vick's. Some love them, some don't. I've had OK, but not great interactions with Vick's. YMMV

Midwest-Bayless is not discussed much on the forum, but I've had good luck with them also.

Kirk

[samakijoe]

The size of the plug is 12mm x 1.25 mm.
I found some (set screws) at screw suppliers but they cost about $8 a piece. (not a big seller I guess)
I bought a bolt that size and planed to make plugs with a
dremel tool with a slot on top to install them with lock tight .
You could just cut the bolts you take out of the head to make the plugs.
Out of curiosity I ran the motor with one of the bolts out of the head.
Nothing come out of the open hole.

[TNfiat]

Arik: I have been in touch with Vandor on another item so glad to support the members.

klweimer: thanks again for the vendor list. The Bayless rings a bell from 29 yrs ago for parts back when my daughter was using it. In fact I still have one of their paper parts catalogs when you use to order by phone and they would ship the part, ie no online ordering back then.

samakijoe: that is an excellent idea - I did buy some bolts in case I can't find the plugs but they are too long. I may try your idea about creating a plug with a dremel. BTW I am not an expert on smog control systems but I suspect that the port may have been plugged so therefore nothing came out when you ran the engine.

Thanks again to everyone that responded.

[vandor]

These are the plugs:

https://autoricambi.us/products/cylinde ... n-plug-set

[TNfiat]

Ordered a set from Autoricambi - thanks Csaba

[carl]

They are the same size as the Fiat wheel bolts. Back in the day I made grub screws for these ports by using my Dremel to cut short sections from spare wheel bolts (don't we all have a few hundred of them laying around) and then cutting a screw driver slot in the top.

Odd that running with one removed did not change anything, the port won't affect running since it's exhaust gas after the valve but it will make a hell of a racket since the entire exhaust system is bypassed.