84' Cat to Straight Pipe Q's
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Joined: Sep 2013
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84' Cat to Straight Pipe Q's
Looking at removing the cat on my 84' and putting in a straight pipe. The cat is orginal and I'm pretty sure it's clogged. I still have AIR and it looks like a heat tube is going to the cat. What are my options for this tube? Would I just let blow free or would I need to weld it into the new pipe?
Here's pic I found of the stick set-up.
Thanks
Here's pic I found of the stick set-up.
Thanks
Safety Car
Joined: Apr 2011
Posts: 3,660
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There have been a variety of solutions to this question...
mine would be to:
A. IF you keep the AIR system intact on the engine, find out how to keep the air switching valve stuck in sending air to the manifold or its dump muffler pipe NOT the eng exhaust. I'm sure there is an easy way to jumper the elec connection to do that.
B. remove all the AIR system and get a pump delete. No cat, no need to have a pump. You're not going to fool anybody..
C. weld the air pipe to the "test-pipe" for funzies...
I hesitate to let any d/c parts just 'hang' open. That's a way for contamination to enter. It may be a useless dead end but openings let water/dirt enter where it should not. I'm just a little phobic about that...
mine would be to:
A. IF you keep the AIR system intact on the engine, find out how to keep the air switching valve stuck in sending air to the manifold or its dump muffler pipe NOT the eng exhaust. I'm sure there is an easy way to jumper the elec connection to do that.
B. remove all the AIR system and get a pump delete. No cat, no need to have a pump. You're not going to fool anybody..
C. weld the air pipe to the "test-pipe" for funzies...
I hesitate to let any d/c parts just 'hang' open. That's a way for contamination to enter. It may be a useless dead end but openings let water/dirt enter where it should not. I'm just a little phobic about that...
Racer
Joined: Apr 2010
Posts: 372
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From: Harper Woods MI
On my '84, I removed my cat, gutted the Air Pump and removed the tubes from the exhaust manifolds. I had a garage spot weld over the holes on the exhaust manifolds.
Since I don't have the cat, the tube to the cat was also removed. You can plug the tubes, but I opted for a cleaner engine compartment.
I also live in a no emission test state.
Since I don't have the cat, the tube to the cat was also removed. You can plug the tubes, but I opted for a cleaner engine compartment.
I also live in a no emission test state.
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Joined: Sep 2013
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Thanks for the responses so far. I don't live in a place where emissions rules are issue.
Pezter22..... I assume you left the AIR pump on? What exactly did you gut? I assume you can either weld over the holes on the mainifolds or you can buy a screw in cap if I'm correct? Did you get any codes when you did yours? Did you notcie much difference in noise?
Thanks again
Pezter22..... I assume you left the AIR pump on? What exactly did you gut? I assume you can either weld over the holes on the mainifolds or you can buy a screw in cap if I'm correct? Did you get any codes when you did yours? Did you notcie much difference in noise?
Thanks again
On my '84, I removed my cat, gutted the Air Pump and removed the tubes from the exhaust manifolds. I had a garage spot weld over the holes on the exhaust manifolds.
Since I don't have the cat, the tube to the cat was also removed. You can plug the tubes, but I opted for a cleaner engine compartment.
I also live in a no emission test state.
Since I don't have the cat, the tube to the cat was also removed. You can plug the tubes, but I opted for a cleaner engine compartment.
I also live in a no emission test state.
Racer
Joined: Apr 2010
Posts: 372
Likes: 23
From: Harper Woods MI
Remove the Air Pump and remove the back of the unit and break the plastic fins (blades) inside the Air Pump. Basically you are gutting the unit.
Remount the Air Pump and attach the original serpentine belt.
There is an Air Pump delete pulley, but that will only fit the L98 engines. I've seen '84's with the Air Pump removed and it is possible by using a shorter serpentine belt, but it really looks odd.
You can keep the tubes on top of the exhaust manifolds and cap the pipes at the inlet in the front. I am not aware of the size of the cap, but I have seen it from others who have posted on the Air Pump delete.
Others who have done the delete have not received any codes. I haven't yet. I like that I can finally reach all my spark plugs without the air tubes getting in the way.
Here is a photo of my engine compartment. Air Pump is still there and the exhaust manifolds have been spot welded after the tubes were removed.
Remount the Air Pump and attach the original serpentine belt.
There is an Air Pump delete pulley, but that will only fit the L98 engines. I've seen '84's with the Air Pump removed and it is possible by using a shorter serpentine belt, but it really looks odd.
You can keep the tubes on top of the exhaust manifolds and cap the pipes at the inlet in the front. I am not aware of the size of the cap, but I have seen it from others who have posted on the Air Pump delete.
Others who have done the delete have not received any codes. I haven't yet. I like that I can finally reach all my spark plugs without the air tubes getting in the way.
Here is a photo of my engine compartment. Air Pump is still there and the exhaust manifolds have been spot welded after the tubes were removed.
Racer
Joined: Apr 2010
Posts: 372
Likes: 23
From: Harper Woods MI
Here is a reverse angle of the engine compartment. Notice on the Air Pump there is a threaded plug inserted in to the Air Pump. With the tubes removed the inlet into the Air Pump needs to be capped.
