Smog Pump

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C10MixMaster

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the top bracket is also the bottom bracket for the alt.
 

Finkaire

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Smog pump, electric carburetor argh, if anyone knows of a replacement carburetor, California compliant let me know.
Thanks
 
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scenic760

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Smog pump, electric carburetor argh, if anyone knows of a replacement carburetor, California compliant let me know.
Thanks

I'm actually using the MSD Atomic EFI which is California compliant...seemed almost easier to me to program the EFI than keep jacking around with an emission carburetor..?!

Although apparently I will still need a smog pump...so stupid
 

SirRobyn0

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I finally got to take some pics this afternoon, so now that you have seen the way it goes together from Ben, here it is on my truck. Honestly this is about the best you can get for on the truck photos without taking the fan and shroud off.
 

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SirRobyn0

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I'm actually using the MSD Atomic EFI which is California compliant...seemed almost easier to me to program the EFI than keep jacking around with an emission carburetor..?!

Although apparently I will still need a smog pump...so stupid
I disagree with the smog pump being stupid. Some modern cars still use them, but times they are usually electric now. The smog pump helps the catalytic converter work on a normal day and if you had an issue causing unburned fuel to make it to the exhaust like a misfire will, the smog pump will help that stuff get burned off and reduce damage to the cat. My point if a guy were to be running no cats, then I don't see an issue with taking the pump off even though it does do some work on it's own. But if you have a cat, on a vehicle that originally came equipped with an air pump, then it is best to have it on a functional.
 

Finkaire

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EFI looks like the ticket
Thanks!
 

Ellie Niner

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I managed to get a few pictures from above and below at different angles, but as @SirRobyn0 alluded to, it's pretty hard to get in around everything to take decent photos. Alas, my steaming pile of computer ain't playing nice... I've tried about three times to attach 'em, but it ain't happening. If y'all need the views from down below, lemme know, and I'll see if I can post them from something else.

@C10MixMaster Thanks for the pictures you took. From your second shot, I can see where that extra bottom bracket hanging loose on mine is supposed to go. Appreciate it!
 
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Jeff Lewis

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In Missouri you just get a historic plate so you don't have to have an inspection.
 

fast 99

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here is a link to a downloadable factory manual from the reference section on GMSB

page 845 section 6E-16 has a drawing of the pump and brackets
New here, do I need to download media fire to open these files?
 

fast 99

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81 350 K20
 

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scenic760

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I disagree with the smog pump being stupid. Some modern cars still use them, but times they are usually electric now. The smog pump helps the catalytic converter work on a normal day and if you had an issue causing unburned fuel to make it to the exhaust like a misfire will, the smog pump will help that stuff get burned off and reduce damage to the cat. My point if a guy were to be running no cats, then I don't see an issue with taking the pump off even though it does do some work on it's own. But if you have a cat, on a vehicle that originally came equipped with an air pump, then it is best to have it on a functional.

I REALLY appreciate everyone's input, pics and guidance on this!! It looks like I was missing the lower alternator bracket from the start...the donor I got the smog pump from (I think it was an '82 Impala) had the "voodoo bracketry" that probably has connections for yet more smog stuff.

On the smog pump being stupid, my thought was that with EFI being controlled by an O2 sensor and a computer is going to be WAY more effective controlling unburnt fuel than 40 year old vacuum technology because its addressing it at the fuel input source...essentially it's leaning/riching out the mixture before it ever enters the engine on every revolution...I do see your point on the smog pump just being another avenue to burn off unburnt fuel....and with a cat replacement at $550- probably not a bad idea!
 

SirRobyn0

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I REALLY appreciate everyone's input, pics and guidance on this!! It looks like I was missing the lower alternator bracket from the start...the donor I got the smog pump from (I think it was an '82 Impala) had the "voodoo bracketry" that probably has connections for yet more smog stuff.

On the smog pump being stupid, my thought was that with EFI being controlled by an O2 sensor and a computer is going to be WAY more effective controlling unburnt fuel than 40 year old vacuum technology because its addressing it at the fuel input source...essentially it's leaning/riching out the mixture before it ever enters the engine on every revolution...I do see your point on the smog pump just being another avenue to burn off unburnt fuel....and with a cat replacement at $550- probably not a bad idea!
Yes, my point exactly, Cats can be expensive and the air pump in a way helps to protect it. Certainly you are right, a EFI system is going to be more efficient than carb, but some vehicles still get an electric version of a smog pump, so they are proven effect I think!
 

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