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70's 242 air smog pump delete?

The above stories are spot-on, and contribute to the public perception that "all old cars stink"... which we are privileged to know doesn't have to be true.

What I'm hoping: whenever you have a choice between making your existing car stink less or stink more... please consider the former. The impact is much greater than you think.

(No drop of rain believes it's responsible for the entire flood.)
 
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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?
The primary goal of modifying the vehicle is to enhance its aesthetics. One critical modification is i will be installing modern catalytic converters, which, unlike their predecessors, do not require (as much) oxygen but rely more on heat and abundance of metals for efficient operation. These newer catalytic converters are highly effective at reducing emissions and offer a significant improvement over older models, which I feel justifies their use in place of the original emission control components.

Removing the air smog pump although is a contentious issue. This component, responsible for injecting air into the exhaust system to aid in the oxidation of unburned hydrocarbons, can often become a source of frequent malfunction. Given that the air smog pump is prone to failure and its repair or replacement can be costly, its removal could be a pragmatic decision. The cost of maintaining this component, which may fail more frequently than desired, could be better allocated elsewhere in the vehicle's maintenance budget.

Moreover, the decision to modify the vehicle should not be seen in isolation. The car's performance metrics, such as a 0-60 mph time of 15 seconds and a curb weight exceeding 2,500 pounds, underscores the necessity of even a fractional increase in horsepower “.01 horse power”. - "this is sarcasm" While the primary motivation may be the enhancement of the vehicle's visual appeal, creating some room for more spacious performance improvements in the future is also a consideration. Even marginal gains in horsepower havemaybe possibly have a very small but possibly noticeable impact on driving dynamics.

From an environmental perspective, the argument for removing the air smog pump is balanced by the car's overall emissions footprint. And while the removal of the air smog pump might seem counterintuitive, it is essential to consider the broader context of the vehicle's environmental impact. With around an average of 5 tesla vehicle sales per day, which replace x amount of cars on the road daily, is significantly more impactful than one volvo creating alittle more dust in the air. Additionally world wide vehicles only produce around 3 billion metric tons of co2 yearly, while mega corps and industrial manufacturing creats around 36.8 giga-tons. (1 giga-ton = 1,000,000 metric tons). I additionally own and operate a pre-epa diesel work truck "this is required by my job" which has a far greater environmental impact compared to the modified Volvo. Given the disproportionate emissions from the diesel truck, the overall ecological footprint of the Volvo, even with the air smog pump removed, remains relatively unimportant to anyone on this thread or any governing body of anywhere.

The decision to remove the air smog pump while upgrading other components, such as installing modern catalytic converter hopefully reflects and shows I'm trying to balance between visual enhancement and environmental responsibility. The motivations behind these modifications are rooted in both practical considerations, such as reducing maintenance costs and improving vehicle aesthetics, and maybe giving the engine bay more room for my mechanic elfs to work there magic. where as the vehicle's impact is completely unimportant compared to other sources of pollution.
 
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My Toyota Matrix with the 2zz-ge engine was the first model year, 2003, no smog pump, but all later years had a smog pump until 2008 when they ditched that motor because they couldn't make it clean enough. I do have a ULEV sticker on the window somehow.
 
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.
All modern cars switch off the compressors above a couple setpoints: sustained and peak RPM. If peak compressor speed is 5000 RPM, the AC request signal will be turned off shortly before that speed; if the sustained max RPM is 4000-4999 rpm compressor speed, the ECU will shut off the AC request signal after a certain countdown timer value is reached. It can get fancier than that with logic that takes multiple instances of sustained high speed total operation over a set period of time, for instance.

It’s all set up very conservatively; you will likely never experience problems related to operating speed.
 
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.
Pretty sure most people just slap carbs on and deem them good enough out of the box.
 
Pretty sure most people just slap carbs on and deem them good enough out of the box.
Why would they throw a cat on a 1960 V8? That just restricts the exhaust, and in CA you can only buy CA legal cats, and have them installed by a licensed shop. I'm sure most carbureted vehicles will never get a cat installed in CA because it costs more and hurts performance on you 5L that makes 220 HP. So no cat and running way too rich
 
Why would they throw a cat on a 1960 V8? That just restricts the exhaust, and in CA you can only buy CA legal cats, and have them installed by a licensed shop. I'm sure most carbureted vehicles will never get a cat installed in CA because it costs more and hurts performance on you 5L that makes 220 HP. So no cat and running way too rich
I don't think anyone is advocating for adding a cat to a car that didn't have one originally. It is more that most folks shouldn't be trusted when they are in the same room as a screwdriver and carbureted engine.

The matter of performance in malaise era V8s is more a function of really conservative ignition timing, rather lean mixtures, low compression, and lame camshafts. Foolhardy attempts to make a quadrajet run clean enough to pass an idle only test.
 
All modern cars switch off the compressors above a couple setpoints: sustained and peak RPM. If peak compressor speed is 5000 RPM, the AC request signal will be turned off shortly before that speed; if the sustained max RPM is 4000-4999 rpm compressor speed, the ECU will shut off the AC request signal after a certain countdown timer value is reached. It can get fancier than that with logic that takes multiple instances of sustained high speed total operation over a set period of time, for instance.

It’s all set up very conservatively; you will likely never experience problems related to operating speed.
I doubt anything Ford came up with can keep up with the way the 5.0 Coyote V8 revs. The compressor clutch wouldn't have time to release. Fortunately, they do have a good rev limiting system on the 4th generation engines.
 
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.

You do realize your first statement ^^ makes you sound like an ignorant hack? Not sure if that was intentional.

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?

Your continuation in this vein ^^ strongly alludes to a complete cluelessness about engines or emission controls or modifications in general.

One critical modification is i will be installing modern catalytic converters, which, unlike their predecessors, do not require (as much) oxygen but rely more on heat and abundance of metals for efficient operation. These newer catalytic converters are highly effective at reducing emissions and offer a significant improvement over older models, which I feel justifies their use in place of the original emission control components.

Two days later, this ^^ tells a vastly different story.

You could have steered this entire thread differently if you had divulged that in the first place...
 
Early type Two-Way Cats require additional O2 and can not function with continuously rich mixture. That's why the need for the Air Pump.
The later Three-Way type needs the the mixture that switches near the stoichiometric point and that can only be done with the O2 sensor. So simply slapping the Cat on the carbed motor without A/F ratio control will surely kill the Cat, same as removing the Air Pump.
 
If you really want to clean up old cars emissions, install modern fuel injection and a modern cat. Even the older megasquirt (properly installed and tuned) will give better MPG, power, emissions, minor weight reduction, etc.
Fuel systems based on mechanical delivery from a metal toilet flap or carbs are never going to burn very clean.
 
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