Manifold Question

[JPSmit]

This Pic shows the exhaust manifold that came off the car. The next post contains the manifold I was given and is the subject of my question.

Thanks

 

[JPSmit]

This is a Pic of a manifold I was given. Here are my questions.

1. Top arrow. What is that?

2. Bottom arrow. Why the bolt there?

Please note that while the castings appear to be the same neither of those two holes are drilled in the original.

Help!

 

[tony barnhill]

1. EGR Valve

I think the 2nd manifold is off a later 1500 car ('77-'80)

 

[JPSmit]

what's an EGR valve?

 

[tony barnhill]

Part of our American emissions control crap!

 

[Morris]

The bottom arrow/bolt is the port for the air pump. The theory is that when your carb runs too rich, the air pump will put extra oxygen in the exhaust inorder to burn up unburnt fuel in the catalytic converter.

The top-a-ma-jig is the Exhaust Gas Recirculation valve. The theory is that putting exhaust gas in the mixture reduces oxygen thus cooling combustion so that less NOX is formed.

Sounds like these two things kinda work against each other, huh?

Don't screw around with those stock exhaust manifolds. They are a waste of time. Get a header. And if you are rightly concerned about emissions, get a good, modern universal catalytic converter (They can be found on eBay cheap) and keep your carb/ignition in tune. Just my $0.02 US.

 

[Guest]

JPSmit - your old manifold is exactly the same as the one on my 76 Midget. The item on the end (near where the exhaust manifold bolts to the exhaust pipe) of your original exhaust manifold is where the EGR valve mounts. There is a pipe from the EGR valve to the intake manifold. My 76 Midget is still 100% original and I can take a few pictures of the carb, intake manifold, & exhaust manifold if you would like some. Just email me your email address. Mine is Tbirdrestr@aol.com. The exhaust manifold you bought is not the correct one for a 1976 49 state Midget. 1975 & the 49 state 1976 Midgets (those sold in all states but Calif.) did not have a smog pump, catalytic converter, or hardened valve seats. They also have a higher compression ration than the 1976 California Midgets and all of the 1977 through 1979 Midgets. The 1976 California Midgets and all of the 1977 through 1979 Midgets have a catalytic converter, smog pump, hardened valve seats, and a lower compression ratio. On 1975 & 49 state 1976 Midgets you need to add a lead additive to the unleaded fuel to help stop valve recession. I hope this info helps. Email me if you would like pictures of my 76 Midget engine.