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I was going to say that an aftermarket cat (very likely due to the car's age) would probably be different than a factory or a 'direct fit' cat.
The ex. manifold air tube should still be used, but the cat air tube may not be applicable in this situation if there isn't a fitting on the cat for it.
 

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Yes, on my 92 Daytona, which did not have an air pump, but had a single aspirator hose from airbox to catcon, with a 1-way valve, it fed into the passenger side of the catcon.
 

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Discussion Starter · #23 ·
I was going to say that an aftermarket cat (very likely due to the car's age) would probably be different than a factory or a 'direct fit' cat.
The ex. manifold air tube should still be used, but the cat air tube may not be applicable in this situation if there isn't a fitting on the cat for it.
WaltI think you are 'spot on.' the description from AllanC applies to a OE replacement. Mine is not OE.
As I earlier stated, there is a fitting on the end of the ex. manifold (where it connects to the cat) where the smaller tube w/check valve goes. There is a smaller hole with no fitting on top and slightly off center. I can only presume that the longer tube w/ check valve goes there. I hope it connects up in some way, shape or form.

If I connect that longer curved tube, I may have to bend it a bit to get that hose to connect. Necessity is the mother of invention, so this gonna be funtime! LOL I will let you know more when I get that longer, curved pipe w/ check valve. Thanks, Walt!!
 

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Discussion Starter · #24 ·
I was going to say that an aftermarket cat (very likely due to the car's age) would probably be different than a factory or a 'direct fit' cat.
The ex. manifold air tube should still be used, but the cat air tube may not be applicable in this situation if there isn't a fitting on the cat for it.

Well, I got the longer pipe today, and as we suspected and spoke about earlier, there is no opening on the passenger side of the cat converter, since the replacement is a universal fit. So my question is this:

Can the check valve side be connected to the correct hose and the end with the threaded nut be plugged or what??? Thanks Walt for the help!
 

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Well, I got the longer pipe today, and as we suspected and spoke about earlier, there is no opening on the passenger side of the cat converter, since the replacement is a universal fit. So my question is this: . . .
In post #17 you indicated that there was a plug in the catalytic converter on the driver side of the unit. In post #18 I proposed that the converter may have been 180 degrees off from the correct orientation. Remove that plug and see if the threaded end of the longer pipe will fit. If it does then you know that the catalytic converter needs to be rotated 180 degrees.

. . . Can the check valve side be connected to the correct hose and the end with the threaded nut be plugged or what??? . . . .
At engine startup air from the air pump is directed to the exhaust pipe at its junction to the exhaust manifold. After the engine reaches operating temperature the diverter valve sends air to the catalytic converter through this longer pipe. Plugging it will cause a drag and probably failure of the air pump. If you are not going to use the air injection system and connect it properly as originally designed, I would just remove the belt and not allow the air pump to operate. No need to plug any components.
 

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Discussion Starter · #26 ·
It's my understanding that the open ports will create noise. That's what I have been told. OK, don't plug the end o the longer pipe. Am going to have to take to the shop and have them raise the car to get a closer look at what's there. BTW, a direct fit cat is as high as 200 dollars!!! See photo. Is this type of converter what I need???

cat — Postimage.org (at https://i.postimg.cc/Dz8zkL9t/cat.jpg )
 

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. . . It's my understanding that the open ports will create noise. That's what I have been told. OK, don't plug the end o the longer pipe. . . . .
Open ports will create noise because the air pump will push air through them. And you cannot plug them. Your are correct.

. . . Am going to have to take to the shop and have them raise the car to get a closer look at what's there. BTW, a direct fit cat is as high as 200 dollars!!! See photo. Is this type of converter what I need???

cat — Postimage.org (at https://i.postimg.cc/Dz8zkL9t/cat.jpg ) . . .
Yes you will need a closer inspection to determine exactly what you have in terms of a catalytic converter that was installed on the car. Again in post #17 you indicated there was a plug on the side of the converter. You will need to verify this. And if a plug is present, if you remove the plug will the port mate to the threaded fitting on the long, air supply pipe you purchased.

This image shows a curved, external pipe on the side of the converter housing. It does not show a threaded fitting. So to use this style of converter something will have to be fabricated to connect the long, curved air pipe to this curved nipple. You CANNOT use a rubber hose to connect because of the proximity to a very high heat source at the converter.
 

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Discussion Starter · #28 ·
OK. I'm going to get under the car again and look closely at what appears to be a plug or something on the drivers side. Your earlier post spoke of something on the passenger side and that the converter might have been installed 180 degrees off. Here's another picture of a converter that would fit my car. See the obvious opening on the side. Is this what I need? Sounds like I'm going to have to replace the converter again. Thanks again for your help. Next time, let's try and talk in real time using Facebook Messenger.

cat2 — Postimage.org (at https://i.postimg.cc/J0r3xGBp/cat2.jpg )
 

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. . . Here's another picture of a converter that would fit my car. See the obvious opening on the side. Is this what I need? Sounds like I'm going to have to replace the converter again. . . . .
Catalytic Converter 1982 FWD with Threaded Fitting.jpg

It appears this replacement converter has a threaded fitting that would fit the long air tube with a mating thread on the end. Can you take a picture of your existing converter on the vehicle and post? Having a picture would definitely help.

I am not on Facebook.
 

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View attachment 27583

It appears this replacement converter has a threaded fitting that would fit the long air tube with a mating thread on the end. Can you take a picture of your existing converter on the vehicle and post? Having a picture would definitely help.

I am not on Facebook.
The OEM catcon for my 92 Daytona had a threaded fitting for the aspirator tube, but all replacement catcons had a capped tube, and the cap had to be cut off, and a length of silicon hose clamped on to connect it.
 
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. . . . The OEM catcon for my 92 Daytona had a threaded fitting for the aspirator tube, but all replacement catcons had a capped tube, and the cap had to be cut off, and a length of silicon hose clamped on to connect it. . . .
Good idea. If silicone hose is more heat resistant then this seems the way to go. Use the hose to make a universal connection between the catalytic converter port and the supply pipe.
 
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