• Hello Guest, welcome to the initial stages of our new platform!
    You can find some additional information about where we are in the process of migrating the board and setting up our new software here

    Thank you for being a part of our community!

70's 242 air smog pump delete?

1976Flying_Br1k

1976Flying_Br1k

New member
Joined
Aug 23, 2024
Location
Post Falls ID
Afternoon folks. I've been scrolling through threads and looking up various different ways to ask this question with no success so I might as well make a thread myself!

How important is the air/smog pump really? I live in the US in Idaho where emissions are not enforced. I was thinking about removing my smog pump to maybe get some more power out of my n/a b21 engine. And here are afew questions I have.

Is it required for the engine to run?
Does it add power, or is it a parasitic draw on the engine?
Is there something I need to do to delete it, like special manifolds or a different ECU?
Has someone already done it and I am just a dunce?

If you have any questions feel free to ask. This is my first thread and am unsure if I'm doing this right. Or asking the question properly.

Thank you!
 
Jack said:
No
Parasitic draw
Everything attached to it
No
Yes lots of people, idk if you’re a dunce
Click to expand...
If I do remove the air smog pump would it be wise to also update the catalytic converter. I know the old converters needed O2 to properly operate. If the pump failed some would begin to clog up and cause issues. Do you by chance know if I would need to update_delete the CAT?
 
I wish this old wives tale would die, but it never will.

The smog pump requires almost zero power from the engine. It is moving air along a tube; it is not pressuring said air. It is not an air compressor. It is not doing any significantly challenging "pumping" work, despite what we normally think of the word pump.

Remove it if you insist, you'll have to change several other things as well, and you'll magically unlock at least 0.01 horsepower. Or leave it as is, it doesn't harm a thing, it helps the cat run much more efficiently (as you alluded to.) And even if you don't give a carp, your kids/grandkids will appreciate cleaner air. Not to mention anyone stuck driving behind you.

Here's the real problem: the more we intentionally are willing to make cars run dirty, the more ammunition the average Joe Public has to think poorly of "old cars" and by extension all automotive enthusiasts, and the faster they can convince their elected representatives to shut us down. It's already killing CA, do you really want this public perception disease to spread to you also?
 
Smog pumps just dilute the air so tailpipe emissions are “cleaner” the engine still puts out as many baddies as it does without a pump.

More complex the system the worse it is for maintenance.

I don’t recommend anyone remove the cat. Even on my smog exempt cars I run them.

Ca is killing old cars because new cars bring higher taxes. Average joe doesn’t know shit about cars or even cares.
If this was about the environment ca would only care about what’s coming out of the pipe and not what’s under the hood.
 
I thought that the smog pump was suppose to pump in oxygen, non-inert gas, into the exhaust to help burn off the unburnt fuel vapors and get the cat up to temp faster. I've had 2 BMW's with air pumps and both only ran on startup, just getting the cat up to temp is what I understand.
 
OVERDRIVE said:
I thought that the smog pump was suppose to pump in oxygen, non-inert gas, into the exhaust to help burn off the unburnt fuel vapors and get the cat up to temp faster. I've had 2 BMW's with air pumps and both only ran on startup, just getting the cat up to temp is what I understand.
Click to expand...
You’re right
 
Jack said:
Smog pumps just dilute the air so tailpipe emissions are “cleaner” the engine still puts out as many baddies as it does without a pump.
Click to expand...

That statement has a tiny kernel of truth: the engine still puts out baddies. The mechanism is not dilution, it's an actual chemical change: a gentle influx of O2 helps the cat render a lot of them harmless, so the end result is overwhelmingly positive. When you compare the pre-cat and post-cat levels of baddies, the numbers are truly astounding.

The benefit is far more real than theoretical. Ask anyone who grew up in LA in the 1960s -- they'll tell you about smog in the basin so thick you couldn't even tell there were mountains until the rainy season came. They'll tell you about swimming, the need to take a deep breath before diving in the water, and that the human body literally refused to suck in that air. The Clean Air Act of 1970 actually worked. It's what's happened since then that becomes ever more questionable, politically.

Jack said:
I don’t recommend anyone remove the cat. Even on my smog exempt cars I run them.
Click to expand...

Good for you, thank you. Me also. And I know there are a bunch more of us here.

Jack said:
CA is killing old cars because new cars bring higher taxes. Average joe doesn’t know shit about cars or even cares.
If this was about the environment ca would only care about what’s coming out of the pipe and not what’s under the hood.
Click to expand...

Many issues there, all true. Especially about caring what comes out of the tailpipe, which they've completely lost sight of.

The main point I see is public acceptance. If you see even a small handful of "old cars" running around belching filth into the air, it becomes really easy to assume they all do it. It only takes one person at the state capitol get their shorts in a bunch, at which point it's a slippery slope of ever-increasing regulations and hurdles. This is what CA has seen. Someone wanted desperately to outlaw all old cars, they knew they couldn't do it overtly, but they nevertheless found a way to make it economically unviable to keep them. The resulting population transfer from streets to junkyards indicates they won the war. Game over... or at least darn close.

Jack said:
Average joe doesn’t know shit about cars or even cares.
Click to expand...

True... all the more reason that it's important for those of us who do know and/or do care to become educated. We need to lead by example. This is our own future hobby we're saving.
 
  • Like
Reactions: PCH
FYI early catalytic converters were two way. They didn't use an O2 sensor on the engines and that type of converter is no longer manufactured. If your engine isn't using an O2 sensor then keep your old two way converter. You won't be able to replace it. Also if you install a new three way converter. It will burn up with the excess emissions from the engine. Without an O2 sensor to keep things in check.
 
it would seem we're on the same page.

even in the 90s LA basin was smoggy where you couldn't see the mountains. Clean air act did clean that up but LA is a natural smog basin where air is stagnant. By the 90s major pollutant was the port industry, mainly tractor trailers used to haul freight from port to staging areas … instead building the proposed short rail system that would do the same but reduce the emissions

last person to help old cars in Ca was Governator, I dont care to educate average person about cars or emissions. When someone who doesn’t know about cars starts telling me about smog and how good for the environment their Prius (name any car) I start to feel the same way as when my overweight doctor was telling me about healthy food choices

I removed my smog pump for simplicity

😘
 
Jack said:
Smog pumps just dilute the air so tailpipe emissions are “cleaner” the engine still puts out as many baddies as it does without a pump.

More complex the system the worse it is for maintenance.

I don’t recommend anyone remove the cat. Even on my smog exempt cars I run them.

Ca is killing old cars because new cars bring higher taxes. Average joe doesn’t know shit about cars or even cares.
If this was about the environment ca would only care about what’s coming out of the pipe and not what’s under the hood.
Click to expand...
It's about emissions, always has been. California was a trend setter. Yes, it cramped the style of those of us that owned high performance cars that had absolutely zero emissions related equipment on them from the factory. Go to a 1970's or older cruise night sometime and you will appreciate what CA did for the rest of the nation by highlighting how bad we all were treating the environment we live in. I went to the Function For Junction several years ago and stood on the sidewalk watching the 1970s and older cars drive by. It was great seeing all the classics, hot rods and muscle cars out of the garage and on the street where everyone could drool over them. The flip side of that was the air was so full of unburned fuel it made me sick, literally. After 45 minutes of my eyes stinging, an intense headache and my stomach twisted into a knot we had to leave. It really made me appreciate how far we have come in the right direction.
This weekend was an Autocross double header with my local club. There were plenty of all out race cars there burning 110 octane race gas with zero emissions equipment on them. Guess what, they all got beat by cars like I own with all the emissions equipment intact, quiet exhaust systems and creature comforts still installed. I have to remember to turn off my AC before the starter drops the flag to start my run. The truth is, I'm always quicker through the course if I forget. I think the AC dampens the power onset which keeps the tires hooked to the pavement. I like to turn it off because the compressor shouldn't be turning 7,500 RPM. I'm betting it has a built in off switch based on throttle, however, I have never looked in to it.
 
Last edited:
Jack said:
it would seem we're on the same page.

even in the 90s LA basin was smoggy where you couldn't see the mountains. Clean air act did clean that up but LA is a natural smog basin where air is stagnant. By the 90s major pollutant was the port industry, mainly tractor trailers used to haul freight from port to staging areas … instead building the proposed short rail system that would do the same but reduce the emissions

last person to help old cars in Ca was Governator, I dont care to educate average person about cars or emissions. When someone who doesn’t know about cars starts telling me about smog and how good for the environment their Prius (name any car) I start to feel the same way as when my overweight doctor was telling me about healthy food choices

I removed my smog pump for simplicity

😘
Click to expand...
Although Arnold was the one that froze the rolling 30 year old smog exemption in 2005. We'd have a smog exempt 240 paradise by now if not for that.

I guess though the fact that you have to smog them has kept the number of stupid hood dump exhausts down.
 
Last edited:
spock345 said:
I guess though the fact that you have to smog them has kept the number of stupid hood dump exhausts down.
Click to expand...
I have seen entirely too many (i.e. more than zero) diesels with a hood pipe, tractor flap and huge trail of soot all along that half of the car
 
2manyturbos said:
It's about emissions, always has been. California was a trend setter. Yes, it cramped the style of those of us that owned high performance cars that had absolutely zero emissions related equipment on them from the factory. Go to a 1970's or older cruise night sometime and you will appreciate what CA did for the rest of the nation by highlighting how bad we all were treating the environment we live in. I went to the Function For Junction several years ago and stood on the sidewalk watching the 1970s and older cars drive by. It was great seeing all the classics, hot rods and muscle cars out of the garage and on the street where everyone could drool over them. The flip side of that was the air was so full of unburned fuel it made me sick, literally. After 45 minutes of my eyes stinging, an intense headache and my stomach twisted into a knot we had to leave. It really made me appreciate how far we have come in the right direction.
This weekend was an Autocross double header with my local club. There were plenty of all out race cars there burning 110 octane race gas with zero emissions equipment on them. Guess what, they all got beat by cars like I own with all the emissions equipment intact, quiet exhaust systems and creature comforts still installed. I have to remember to turn off my AC before the starter drops the flag to start my run. The truth is, I'm always quicker through the course if I forget. I think the AC dampens the power onset which keeps the tires hooked to the pavement. I like to turn it off because the compressor shouldn't be turning 7,500 RPM. I'm betting it has a built in off switch based on throttle, however, I have never looked in to it.
Click to expand...
I was just at a cruise night with some friends. I bailed once my eyes started watering and I was getting a headache. I'm also convinced that most folks with those old American cars don't know how to properly tune the carbs. I've beheld big block monstrosities roll by while I'm on the sidewalk and they all smell horrible. Enough unburnt fuel that they can't be running right.
 
You must log in or register to reply here.
Back
Top