AMC Eagle Den Forum

The Mighty 258 => General Service and Diagnosis => Topic started by: idahosx4 on October 17, 2013, 12:34:32 AM

Title: Exhaust Manifold
Post by: idahosx4 on October 17, 2013, 12:34:32 AM
Hi all.

I recently purchased a dark gray '81 SX/4 from the guy who bought it from JSK on the older forum. Man is it gorgeous! I'll be sure to post info and restoration progress when I start taking pictures.

So onto my first question for the forum. On my exhaust manifold, can someone tell me what this extra pipe (on the left in the picture) opening is for? I stole this pic from ebay, but it's the same manifold I have on my engine. Is it related to the air injection system (which is now gone on my vehicle) maybe? The exhaust manifold diagram in my FSM doesn't show it. Does it need to be plugged or hooked up to something? Because it is just open in my engine right now.

(https://dl.dropboxusercontent.com/u/6274941/exhaustmanifold.JPG)

Thanks for the help guys!
Title: Re: Exhaust Manifold
Post by: mudkicker715 on October 17, 2013, 05:00:27 AM
It is supposed to hook up to your air cleaner to help in cold start up. Since the manifold gets hot you get warm air to the carb. After the car is warm it gets bypassed. Its not necessary imo. I do not use them..
Title: Re: Exhaust Manifold
Post by: idahosx4 on October 17, 2013, 09:13:37 AM
Oh, I can see it now, it doesn't actually vent exhaust anywhere, just goes over the outside of the manifold. That helps. I bought the car with a motorcraft carb already on it so that's why mine wasn't hooked up. Thanks!
Title: Re: Exhaust Manifold
Post by: JayRamb on October 17, 2013, 01:11:04 PM
Looking at the picture, there is a tube on the right hand side of the exhaust manifold. I couldn't get the pipe off mine, on the right hand side of the picture. I had to plug the holes in the manifolds. I noticed no difference in performance. It was, I guess, an emissions do hicky.
Title: Re: Exhaust Manifold
Post by: carnuck on October 17, 2013, 02:55:24 PM
EGR pipe. I'm swapping my manifold (if I don't go EFI) to get rid of the AIR pipes. The EGR feeds exhaust gases back to the motor to cut down combustion chamber temps and keep the ping monster away, but by changing to NGK BKR6EK plugs I run mine without it and don't get ping.
Title: Re: Exhaust Manifold
Post by: JayRamb on October 17, 2013, 05:39:11 PM
I have noticed no pinging since I got rid of the EGR pipe.