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post #1 of (permalink) Old 08-05-2003, 06:37 PM
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Need some more emission/smog /exhaust help

Well in trying to clean up the previous owners downfalls and the worn out parts on the new Burb I have run into a vacuum connector and set of small gauge lines that are pretty much all cracked. This is the set of lines that has a connector screwed into the thermostat housing and feed to the EFE, Distr, Manifols vac, and the TVS(air cleaner). Does anyone know a part number on this or where to get one, or should I just run my own routes.

In an earlier post I asked about removing smog stuff and got a couple of replies which were both good ideas, but in the opposite direction on some stuff. But, I decided to try to meet somewhere more toward the OEM smog side.

I am going to detail out the work I am doing to replace stuff that had a problem, and then things I am thinking about doing, if you can please help out with a few of these

Details of the work I am doing to replace broken
1. Replace OEM exhaust manifold - Ordered new Dynomax painted headers headers w/AIR fittings, copper gasket
2. Replaceing CAT and muffler(cracked) - Ordered new high flow on recommendation from bud at the local exhaust shop and the Flowmaster 50
3. Replacing stock Ypipe to fit the new Headers and running new pipe at the tailend. I am thinking 2 1/2" or should I go 3" (I prefer more torque that higher horses)
Ordered new O2 bung and sensor for OEM 1 wire setup to be welded on to the new Ypipe
4. Ran some new vacuum lines for some of the larger rubber type lines from tubing left over from a Harley rebuild.

Things I am thinking of doing, but dont know the which way is good or just a waste of money
1. New air cleaner(open circular Holly or Edelbrock type) to replace stock monster - Is this a good idea or would I be better staying stock (My Jeeps have always benefited from this) and Plug of the vacuum lines that use to go to the air cleaner
This seems like only a few of the emissions components get removed like the TVS and heater hose(gone anyway with the headers)
2. Replace belt driven fan with electric dual fan setup

Well what do ya'll think
86 Burb 350 4bbl Quadrajet
10 bolt front, 12 bolt rear
3.43 ratio and 32's
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post #2 of (permalink) Old 08-05-2003, 07:24 PM
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Re: Need some more emission/smog /exhaust help

Those vacuum switches that are on the water neck do a bunch of different stuff. I recommend tracing them and seeing where they go. I know they made it so AIR and EGR couldn't work when the motor was cold on my truck. It also prevented the torque converter clutch from locking up when cold.

AIR is a pain in the butt in my opinion. So is an APT carburetor. EGR and catalytic converters should be kept though.

2.25" duals or 3" single is all you need for exhaust plumbing.

Why do you have an oxygen sensor if you have a Quadrajet? They never put CCC Quadrajets on trucks.

If you have the big air cleaner (takes a 5" tall element) then keep it. It flows more air than you need. Furthermore, it sucks in cold air. Next, it has a heat riser tube to help cold starts (until you put the headers on anyway).
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post #3 of (permalink) Old 08-06-2003, 12:24 AM
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Re: Need some more emission/smog /exhaust help

Thanks Wrath

Your right when you said "Why do you have an oxygen sensor if you have a Quadrajet? They never put CCC Quadrajets on trucks." when I looked up componets on the store site it showed me needing one, but that was for an 87. Oh well I had not bought the sensor and the bung was only 4bucks so I will go look more closely before trusting a web site next time.
I do have the 5" cleaner and thought it would be better to keep. thanks for comfirming
I have traced all the lines to the water bung vacuum connection. My main thing is that I will need to run new lines since that connector, fittings, and lines are trashed (brittle flaking ruber). I dont have a issue doing it, but thought if someone knew the part # of that assembly or where I could find one I would do that.
I think I will do the 3" single to keep the clutter from underneath the truck, and that lowers my costs on cat's and mufflers.

Thanks again
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post #4 of (permalink) Old 08-06-2003, 09:49 AM
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Re: Need some more emission/smog /exhaust help

I cant help you much since I dont ever recall trying to fix my smog stuff [img]images/graemlins/crazy.gif[/img] It ussually dosnt work so I pitch it.

I believe you can get the funky little wrap around metal deal for your header to keep the warm up thingy.

And like wrath said.....keep the stocker or put a factory 5" on it if you did have a small one.
post #5 of (permalink) Old 08-06-2003, 10:42 AM
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Re: Need some more emission/smog /exhaust help

A great deal of what you do to it depends on whether you drive it in the street or not, and what your local smog laws are.
Remember, your county may not be doing smog testing in Texas - yet! But some are. That's why in the counties that are doing smog testing you can get a great deal on some rigs that have been modified and can no longer be licensed.

Politicians make the rules on smog testing - not real, practical, or honest people, so you are at their mercy.
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