Are any emissions components GOOD to keep? (+Snorkel components)

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AuroraGirl

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So I found my 400 snorkel and I think I'm gonna put it on my truck and fix thr duct work to my fresh air inlet. (Is this easily buyable?) It has the wide snout, not the puny circular one. It goes to the left. If I have the right hose laying around, I'd prob install an original breather tube too, so it's not its own thing on the valve cover. But thats just if I have one.

But, it has the heat flap in the snout that I would have to remove or something. But if it is beneficial, I'd like to keep it. I heard it helps engine warm quicker in winter??? Also, there is that switch on the inside that I never understood what it does. Has vacc lines to it. The only car I had a air cleaner with was my 77 LTD. Naturally, being a Ford, it didn't work right. Especially a 400 modified ford. Bad choices were made. Had a c6 tho!

Anyway, I also would need an air filter. Are they measured in inches or do I need a height measurement too?

And lastly, is there any emissions components that were beneficial or positive that I might have laying around or easy to put on? For me, I'd like to put a charcoal canister back in but that's the only thing I can think of, but anything else?

I have plenty of air cleaners, 4 of them for 4 barrels and about 3 to 5 for 2 barrels.(could they be made to fit 4 barrels?)
 

Ricko1966

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I would want properly operating egr and air cleaner heat. Cold air fuel is denser so it makes more power but warm air fuel gets better mileage and prevents carburetor icing. EGR everyone says get rid of it, but most don't understand it.EGR is closed when you need power, just like it wasn't there.At cruise conditions it partially fills the cylinders with inert gas so your cylinders don't fill as completely with fresh air and fuel.The cylinders full it just doesn't have as much gasoline in it. EGR benefits. Better mpg, cooler cylinder temperatures and less knock prone,When your setting up a distributor you can run 2-4 degrees more timing than a non egr car.
 

Turbo4whl

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I would want properly operating egr and air cleaner heat. Cold air fuel is denser so it makes more power but warm air fuel gets better mileage and prevents carburetor icing. EGR everyone says get rid of it, but most don't understand it.EGR is closed when you need power, just like it wasn't there.At cruise conditions it partially fills the cylinders with inert gas so your cylinders don't fill as completely with fresh air and fuel.The cylinders full it just doesn't have as much gasoline in it. EGR benefits. Better mpg, cooler cylinder temperatures and less knock prone,When your setting up a distributor you can run 2-4 degrees more timing than a non egr car.

The EGR also sends un-burnt hydrocarbons that would go out the exhaust. This is fuel. With out the designed EGR operation the engine would have a lean mixture when cruising. This is why changing items, like adding headers and a free flowing exhaust system, changes to the carburetor are also needed.
 

1987 GMC Jimmy

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I would keep:
  • PCV Valve because it’s unsightly and unsmell-ly to have crankcase gases and blowby puffing out of a vent. It might be okay on a very healthy motor, but imagine one that’s very tired, or even moderately worn, and looking like Steamboat Willie.
  • Charcoal Canister/purge valve/unvented fuel cap because it helps keep the raw gas smell in a closed circuit. I don’t find that smell hovering around to be appealing.
  • EGR in a vehicle that has an ECM just to avoid dealing with reburning a PROM chip. If it doesn’t have an ECM, I’m okay with keeping it if it works but also deleting it if it doesn’t.
I’m okay with having a manifold stove, riser tube, and thermac working, especially if it’s in a colder climate, but I hate the EFE valves with a passion (noisy bastards) so that’s a big one to get rid of for me. Anything that’s a TVS or delay valve for anything you don’t want can go, air injection can go just because it can also be noisy, and it’s a breeze to get to your mechanical fuel pump with out the smog pump there. So yeah, EFE, AIR and diverter, and all the stupid little TVSs and delay valves can take a hike unless you really need them for something you keep like EGR in a pre-OBD I vehicle.
 

Turbo4whl

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@1987 GMC Jimmy I disagree with you on TVS, Trapped Vacuum Spark. So long as it is working properly it is a system for cold starts in cold climates.

What it does is take vacuum from both the manifold and ported vacuum. Which ever is stronger, this vacuum is held with a check valve to give full vacuum advance when the engine is cold. When the engine warms, the vacuum advance is switched to ported vacuum with no check valve.

There is a cindered iron bleed in the check valve port, so if the engine should stall, or be shut off it will restart with out the vacuum advance being held on. This is where there could be a problem, if the bleed is clogged.

Sure if you advance the initial timing, you may not want this, but then you are not going to pass an emission test at idle.
 

1987 GMC Jimmy

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@1987 GMC Jimmy I disagree with you on TVS, Trapped Vacuum Spark. So long as it is working properly it is a system for cold starts in cold climates.

What it does is take vacuum from both the manifold and ported vacuum. Which ever is stronger, this vacuum is held with a check valve to give full vacuum advance when the engine is cold. When the engine warms, the vacuum advance is switched to ported vacuum with no check valve.

There is a cindered iron bleed in the check valve port, so if the engine should stall, or be shut off it will restart with out the vacuum advance being held on. This is where there could be a problem, if the bleed is clogged.

Sure if you advance the initial timing, you may not want this, but then you are not going to pass an emission test at idle.

I’m referring to the thermal vacuum switches that are married to a specific component: EFE, EGR, and I guess they’re around for distributor delay if so equipped, I don’t have anything with that one. If you’re getting rid of whatever piece of equipment they mediate vacuum for, no point in having them stick around. If you’re planning on keeping EFE, for instance, then yeah don’t get rid of them.
 

Craig 85

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Here's the set up I had on my '79 K15. I did change to the taller air cleaner lid for more air flow. It's 2" taller. The snorkel tube is available from LMC. My truck had all the smog and I believe 150-165 HP stock with all the emissions. It actually ran better with this set up in the summer with the A/C going than with an open air cleaner.

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I would keep:
  • PCV Valve because it’s unsightly and unsmell-ly to have crankcase gases and blowby puffing out of a vent. It might be okay on a very healthy motor, but imagine one that’s very tired, or even moderately worn, and looking like Steamboat Willie.
  • Charcoal Canister/purge valve/unvented fuel cap because it helps keep the raw gas smell in a closed circuit. I don’t find that smell hovering around to be appealing.
  • EGR in a vehicle that has an ECM just to avoid dealing with reburning a PROM chip. If it doesn’t have an ECM, I’m okay with keeping it if it works but also deleting it if it doesn’t.
I’m okay with having a manifold stove, riser tube, and thermac working, especially if it’s in a colder climate, but I hate the EFE valves with a passion (noisy bastards) so that’s a big one to get rid of for me. Anything that’s a TVS or delay valve for anything you don’t want can go, air injection can go just because it can also be noisy, and it’s a breeze to get to your mechanical fuel pump with out the smog pump there. So yeah, EFE, AIR and diverter, and all the stupid little TVSs and delay valves can take a hike unless you really need them for something you keep like EGR in a pre-OBD I vehicle.
do you know how the snorkel stuff(thermac, stove, etc) work and how to set them up? Or if they need replacing
 

1987 GMC Jimmy

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do you know how the snorkel stuff(thermac, stove, etc) work and how to set them up? Or if they need replacing

Sorry for the late response, Taylor. I’ve been very tired at the days’ ends lately. The thermostatic air cleaner system, or thermac, is supposed to have a heat stove shrouding the exhaust manifold, a heat riser tube hooked to the fitting on the heat stove at the bottom and the air cleaner fitting on top (the tube looks like a stiff, mini dryer exhaust duct), and then the air cleaner. The introduction of vacuum should yank the flapper closed, and then the thermostat allows it to reopen once there’s ambient warm air and not just the heat coming off the exhaust. It’s intended to keep warm air flowing into your wet manifold systems (carb and TBI) that need all the help they can get to atomize the fuel, especially in the winter.

The only way they can go bad is the diaphragm or the thermostat. I guess they can seize if they sat up and rusted somehow. If the vacuum lines are good, you can apply vacuum to it and see if the valve closes, either using a hand pump or the engine, to test the diaphragm. The thermostat a watch it and see kinda thing once it warms up. I would have a riser tube on there before I tested it and see what it does, especially in the winter time. I know the system is valuable here in the winter, I can’t imagine how much it is up there.

Also, if you ever want to swap to an “Air Gap” performance intake, you have to have the thermac system in place. Furthermore, if you have headers, you also have to engineer a heat stove for the air gap intake. A user on here, @rich weyand, did it with his truck if you wanna dredge up his stuff. Nice guy and a helluva nice truck he had.
 

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Sorry for the late response, Taylor. I’ve been very tired at the days’ ends lately. The thermostatic air cleaner system, or thermac, is supposed to have a heat stove shrouding the exhaust manifold, a heat riser tube hooked to the fitting on the heat stove at the bottom and the air cleaner fitting on top (the tube looks like a stiff, mini dryer exhaust duct), and then the air cleaner. The introduction of vacuum should yank the flapper closed, and then the thermostat allows it to reopen once there’s ambient warm air and not just the heat coming off the exhaust. It’s intended to keep warm air flowing into your wet manifold systems (carb and TBI) that need all the help they can get to atomize the fuel, especially in the winter.

The only way they can go bad is the diaphragm or the thermostat. I guess they can seize if they sat up and rusted somehow. If the vacuum lines are good, you can apply vacuum to it and see if the valve closes, either using a hand pump or the engine, to test the diaphragm. The thermostat a watch it and see kinda thing once it warms up. I would have a riser tube on there before I tested it and see what it does, especially in the winter time. I know the system is valuable here in the winter, I can’t imagine how much it is up there.

Also, if you ever want to swap to an “Air Gap” performance intake, you have to have the thermac system in place. Furthermore, if you have headers, you also have to engineer a heat stove for the air gap intake. A user on here, @rich weyand, did it with his truck if you wanna dredge up his stuff. Nice guy and a helluva nice truck he had.
is the heat stove a bolt on? Ihave a bunch of manifolds laying around, some have it on. i didnt see how it attaches. by wet manifold you mean gasoline goes past intake valves, yes? so not diesel for example.
 

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Shitcan it all except for PVC and charcoal cannister. Swap to Edelbrock PF4 or LS.
 

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is the heat stove a bolt on? Ihave a bunch of manifolds laying around, some have it on. i didnt see how it attaches. by wet manifold you mean gasoline goes past intake valves, yes? so not diesel for example.

Looks to me like they wrap it around the manifold fairly tightly and then spot weld it or solder it to itself where it pinches together on top.
 

Ricko1966

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is the heat stove a bolt on? Ihave a bunch of manifolds laying around, some have it on. i didnt see how it attaches. by wet manifold you mean gasoline goes past intake valves, yes? so not diesel for example.
By a wet manifold they mean like carb or TBI where fuel and air actually pass through the intake from the same point. Port fuel injection, direct injection etc. Would be dry, nothing going through the main body of the manifold but air. Where this gets messed up is too cold of a wet manifold and the right weather conditions the air and fuel and moisture in the air and fuel will actually form an ice wall that will eventually choke off air and fuel to where the car cannot be driven.Its happened to me twice it's really freaky. All you can do is sit there and wait for it to thaw,It normally happens in temps just above freezing so the moisture hangs in the air and the cool8ng effect of being drawn into the manifold and introduced to the fuel, shtt starts freezing.
 

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The heat stove on mine was a U-shaped sheet metal housing with two small tabs that have holes in them . It looks like the original used the holes in the tabs and some type of expanding rivet to hold the shield on the manifold.

I bought a new heat stove and it had attachment holes in the right places. However, I can’t get the old rivets out of the manifold. The heads are too flush to get pliers on them, and the angle is bad to try to drill them out. I put the job off until colder weather when I need the intake heat.

Bruce
 

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