What have you done to your square lately??

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78C10BigTen

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Ted
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Maybe @78C10BigTen Ted, would know what the old cats are worth?
Cats depend on the age and the vehicle it came off of as to what make up of materials they have in them. Those ol bead blowers usually arent worth much. We have a system that we put the manufacturers numbers off the cat in and it tells us the current market value based on the specific number. Our state also requires a title or registration to the car wich it was removed also. Due to the high theft rate.
 

Grit dog

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Ok I am now guessing the TBI would have trouble with no catalytic converter being in there?
I was actually getting somewhat excited to have a solution to this so easily...but I have not thought about the complications of a TBI set up versus a just carbeurated set up. I imagine the straight pipe solution would be no problem on a carbeurated set up-pre 1987...
You’re not getting it cut with a tubing cutter. No room to spin the cutter around it.
If you actually want to remove and save it, keep chopping u bolts at exhaust mounts until you can get the exhaust system to slide backwards a bit. Then do like the last person did, pry up the already hacked slots in the fat pipe and pull, wiggle, pry, hammer it off in one piece. Then you can jimmy rig it back on.
Back to it, truck will run fine without it. Maybe better. It’s a dumb system with no downstream O2. Actually first year of cats on >8500lb trucks iirc.
If it’s original then it’s quite likely not in the best shape for flow. But icbw.
It has been removed at least once before and really doesn’t look “factory” to me other than it looks like old factory style pellet cats but I’m taking @bucket word for it.

PS you don’t have to take the tank brackets off nor the exhaust if you raise/remove the bed.
At this point it may have been easier to do that. And still could if you don’t want to hack the exhaust.

Although I’ll admit at this point I’m getting a bit confused now what you’re trying to fix. And why.
Regarding what to get to straight pipe it. Also variable depending on the condition of and how the rest of the exhaust is mounted.
If it’s sturdy and won’t move on either of the cat (with it removed) then 2 wide band clamps and a piece of pipe is the easiest although $20-30 more than using u bolt clamps. If you use u bolts or the exhaust needs the support of a rigid connection where the cat is, then you need to reinstall bell n spigot on one or both ends for strength.
This is also the reason I say take the bed off. It’s no harder really than messing with everything else and it makes all the tank work much easier and more accessible. Just replace everything once that is old and/or suspect at once and nothing else to wrestle around (except the bed off course but that takes 1 minute to remove or replace with 4 men.
 

Strick

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Trying to get the big girl some new hue! I'm past ready to drive this '87! AND yes, I'm still using my $10 Hobo Fright gun!!!
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JamesSam

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You’re not getting it cut with a tubing cutter. No room to spin the cutter around it.
If you actually want to remove and save it, keep chopping u bolts at exhaust mounts until you can get the exhaust system to slide backwards a bit. Then do like the last person did, pry up the already hacked slots in the fat pipe and pull, wiggle, pry, hammer it off in one piece. Then you can jimmy rig it back on.
Back to it, truck will run fine without it. Maybe better. It’s a dumb system with no downstream O2. Actually first year of cats on >8500lb trucks iirc.
If it’s original then it’s quite likely not in the best shape for flow. But icbw.
It has been removed at least once before and really doesn’t look “factory” to me other than it looks like old factory style pellet cats but I’m taking @bucket word for it.

PS you don’t have to take the tank brackets off nor the exhaust if you raise/remove the bed.
At this point it may have been easier to do that. And still could if you don’t want to hack the exhaust.

Although I’ll admit at this point I’m getting a bit confused now what you’re trying to fix. And why.
Regarding what to get to straight pipe it. Also variable depending on the condition of and how the rest of the exhaust is mounted.
If it’s sturdy and won’t move on either of the cat (with it removed) then 2 wide band clamps and a piece of pipe is the easiest although $20-30 more than using u bolt clamps. If you use u bolts or the exhaust needs the support of a rigid connection where the cat is, then you need to reinstall bell n spigot on one or both ends for strength.
This is also the reason I say take the bed off. It’s no harder really than messing with everything else and it makes all the tank work much easier and more accessible. Just replace everything once that is old and/or suspect at once and nothing else to wrestle around (except the bed off course but that takes 1 minute to remove or replace with 4 men.
You make great points here Todd.
I can remind you of my truck symptoms but I'm sure it's driving everyone else crazy. Currently I am going after the drivers tank since it hasn't worked in over a year and it needs to be replaced. I then realized the cat is in the way. I feel like removing the bed would be a little too much for me having to work in the drive way. Although that may not have been the case at this point as you ha e observed. If/when I can get the drivers tank and fuel pump, cat(or no cat) replaced I am hoping the shuddering under throttle will have been remedied and I can then begin troubleshooting on passenger side tank. If none of it helps the studder then I can begin at square one again with a new drivers tank and cat with only the old passenger side tank and fuel pump to replace.

So, long story long again initial studdering has led me to start a longer term goal of replacing tanks and sending units. No official diagnosis I just believe it is fuel system or cat related. Also if I had tried to drive it in to a garage the wife would have cut my b***s off. I also was very overwhelmed looking at how much the PO paid in labor costs to just replace the fuel pumps in each tank.
 

Strick

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That looks fantastic! Reminds me of my ole '76 High Sierra.
 

Ajax19

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You make great points here Todd.
I can remind you of my truck symptoms but I'm sure it's driving everyone else crazy. Currently I am going after the drivers tank since it hasn't worked in over a year and it needs to be replaced. I then realized the cat is in the way. I feel like removing the bed would be a little too much for me having to work in the drive way. Although that may not have been the case at this point as you ha e observed. If/when I can get the drivers tank and fuel pump, cat(or no cat) replaced I am hoping the shuddering under throttle will have been remedied and I can then begin troubleshooting on passenger side tank. If none of it helps the studder then I can begin at square one again with a new drivers tank and cat with only the old passenger side tank and fuel pump to replace.

So, long story long again initial studdering has led me to start a longer term goal of replacing tanks and sending units. No official diagnosis I just believe it is fuel system or cat related. Also if I had tried to drive it in to a garage the wife would have cut my b***s off. I also was very overwhelmed looking at how much the PO paid in labor costs to just replace the fuel pumps in each tank.
Just grab the saws all and you can get some pipe and clamps you need at the parts store for reinstall
 

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