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Old 10-11-2010, 01:03 AM   #1
nikwho
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getting rid of smog equipment

Well, I am getting ready to swap in a fresh 383 in my '83. It currently has the old 305. I installed my heddman headers and dropped it off at the muffler shop to get the headers tied into the 2.5" dual exhaust so the exhaust will be ready for the swap. I also ditched the smog pump and all of the vaccum lines that aren't needed. I am now down to only the fuel tank being tied into the big smog canister. My question is, should I cap the line that returns to the fuel tank, put a breather or filter on it? leave it open? im not sure of the bearing that this line has on the fuel system. Thanks, Nik
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Old 10-11-2010, 01:43 AM   #2
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Re: getting rid of smog equipment

Quote:
Originally Posted by nikwho View Post
Well, I am getting ready to swap in a fresh 383 in my '83. It currently has the old 305. I installed my heddman headers and dropped it off at the muffler shop to get the headers tied into the 2.5" dual exhaust so the exhaust will be ready for the swap. I also ditched the smog pump and all of the vaccum lines that aren't needed. I am now down to only the fuel tank being tied into the big smog canister. My question is, should I cap the line that returns to the fuel tank, put a breather or filter on it? leave it open? im not sure of the bearing that this line has on the fuel system. Thanks, Nik
i just left mine open. been ok for about a year now
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Old 10-11-2010, 01:53 AM   #3
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Re: getting rid of smog equipment

I was going to try that, I would just hate for it to get a bunch of dirt and crud in it. Good to know that though. I wonder if it would hurt to block it off???? THanks, Nik
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Old 10-11-2010, 06:23 AM   #4
motornut
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Re: getting rid of smog equipment

i think some need air going in to release the pressure?
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Old 10-11-2010, 06:51 AM   #5
tucsonjwt
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Re: getting rid of smog equipment

You can get a vent cap from Classic Parts. How are you going to pass CA vehicle inspection without all of your smog stuff?
I do not have a vapor recovery canister on my 83 C20 (not required), but I recently routed the short direct vent lines on the sending units back to the rear of the truck, terminating over the spare tire with vent caps. This eliminated the gas smell I was getting in the cab area. The caps are the same ones used for the differential vent (I think) - you can see a third gray cap sticking up from the differential in the bottom of the third pic. Here some pics. You can see the two light gray colored caps over the top of the spare tire (dual tanks).
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Old 10-11-2010, 10:09 AM   #6
nikwho
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Re: getting rid of smog equipment

Thanks. I'll track down a couple of diff vent caps. I appreciate the help
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Old 10-11-2010, 01:04 PM   #7
benoit454
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Re: getting rid of smog equipment

left all the ones I did open no problems. if you plug it off it can build pressure, so either cap it with a filter or plug it and get a vented gas cap.
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Old 10-11-2010, 01:23 PM   #8
Oilbrnr
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Re: getting rid of smog equipment

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Originally Posted by tucsonjwt View Post
You can get a vent cap from Classic Parts. How are you going to pass CA vehicle inspection without all of your smog stuff?
He is not in Pima or Maricopa counties. No emission test required. Thou with the number of tree hug'n nOObs in Flag these days, I'm sure sniff testing is just around the corner...
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