Catalytic converters: does your square have them?

Does your square have a catalytic converter?

  • yes

  • no

  • yes, but only because I couldn't get a sticker/plate without them.

  • no, but only because I'm too lazy/cheap to change what the previous owner did.

  • no, because my truck didn't come with them.


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Catbox

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Peter
Truck Year
1979
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C20 Silverado Camper Special
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461
We don't have vehicle inspections here in Oregon, but like I said above we have DEQ for 1976 and newer.
Right now they are kicking my ass with my 1995 Suburban as it won't pass.
We do get to test for free until it passes though, so there is that small plus.

For the next test, we will be rebuilding the TBI unit.
Hopefully because we have to do it and one of these days it will pass, our gas mileage will get better.
 

SirRobyn0

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Rob
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1984
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C20
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305
We don't have vehicle inspections here in Oregon, but like I said above we have DEQ for 1976 and newer.
Right now they are kicking my ass with my 1995 Suburban as it won't pass.
We do get to test for free until it passes though, so there is that small plus.

For the next test, we will be rebuilding the TBI unit.
Hopefully because we have to do it and one of these days it will pass, our gas mileage will get better.
I've got a good friend in Portland with an 82 MH, Class C w/350 and she had a heck of a time getting it through DEQ two years ago. If you want someone else to look at your failure report and possibly give you thought or two on what might be causing it feel free to PM me with it.
 

SirRobyn0

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I'll admit that I get frustrated with emissions controls at times, but taking a look at pictures of the thick smog blanketing heavy industrial areas in places like China and India, then comparing that with ours... sorta reminds you that there is a valid reason for these devices. China and India are kinda like where we were 50 years ago.
I know what you mean. Another thing that gets me is guys that think they get something from simply removing the EGR valve and putting on a block off plate. Yea, what they get are higher emissions, higher combustion chamber temps, and more pinging, but some will still do it because it's an "emissions control device" all the while not realizing it is so much more than that.
 

Catbox

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Location
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First Name
Peter
Truck Year
1979
Truck Model
C20 Silverado Camper Special
Engine Size
461
I've got a good friend in Portland with an 82 MH, Class C w/350 and she had a heck of a time getting it through DEQ two years ago. If you want someone else to look at your failure report and possibly give you thought or two on what might be causing it feel free to PM me with it.
Right now it is not passing the idle emissions req's.
We have whittled it down, but not to passing as of yet.
Thing idles like a sewing machine at 550 rpm, we will be upping the idle speed before we go back as well.

It may simply be time for a simple rebuild of the heads as the whole unit has over 225K miles on it.
Still runs like a champ, but just has the grocery getter miles on it.

I will keep you in mind if we can't get through after this one.
 

85 Squarebody76

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Missouri
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Bob
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1985
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GMC C1500
Engine Size
305
So it was brought to my attention that apparently I'm the odd man out because I have a catalytic converter (2 actually) on my truck.
Just looking to see what's out there on squares.
Yep my '85 has a single exhaust for now and has one cat... working good so far... my '85 is a one owner with 55,000 actual miles on the clock so far.. But that will change...
 

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mikeoverland

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san antonio tx
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michael
Truck Year
1981
Truck Model
C10
Engine Size
250/I6
I once wondered about the lack of an air pump and a cat on the basket case and i found out something interesting. My particular 1981 square was built in Canada (vin starts 2g) and for some reason was exempt from all of that crap. i do kind of have an egr (it's fried) and an evap canister and some air valves that are built into the vavle cover. Now i will be keeping the egr and the evap canister because both of those look quaint under the hood (and neither one works). Now the rest of the vacuume tees and all of the air valves on my valve cover are going to "fall off" the second I get the brakes and the fuel pump done.
 

waterpirate

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delaware
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Eric
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1987
Truck Model
v10
Engine Size
5.7 tbi
I recently removed mine, OG to my 87 to make removing the gas tank possible. Cat blocked any access to bracket bolts. Straight pipe went back.
Eric
 

WebMonkey

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Chris
Truck Year
1985
Truck Model
K20
Engine Size
350
my 1985 k20 super double xtra heavy duty was cat exempt when built in st. louis.

i definitely notice the difference in exhaust stink but i'm ok with that.

;)
 

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