How do I remove Catalytic Converter? 93 Vette
Thread Starter
Heel & Toe
Joined: Oct 2005
Posts: 16
Likes: 0
How do I remove Catalytic Converter? 93 Vette
I'm trying to remove the stock exhaust manifold and catalytic converter. The bolts that connect the exhaust manifold to the exhaust pipe (about 12 inches upstream of the catalytic converter) are difficult to reach. They are a 9/16 bolt that is about 3 inches long. The frame and other components make it difficult to reach up to.
Has anyone removed this before? If so, how did you get it off?
Has anyone removed this before? If so, how did you get it off?
Le Mans Master
Joined: Dec 2006
Posts: 5,139
Likes: 482
From: H-Town Texas
The only one that I've had major trouble with is one bolt on the passenger side to the manifold. The bolt is directly above the motor mount brace. Depending on how rusted in place it is, you may be able to get it with a sturdy swivel, or you can just take that brace off. It's just one piece that bolts to the frame and the cross member and is the supprt for the engine mount.
One of my favorite things about these cars is the amount of disassembly required to get to the actual part you need to.It's quite comical sometimes.
One of my favorite things about these cars is the amount of disassembly required to get to the actual part you need to.It's quite comical sometimes.
Team Owner
Joined: Sep 2003
Posts: 25,397
Likes: 2,742
You need to soak them down well with a penetrating fluid of some sort and you do need to be patient. On a '93 they're metric I believe and you need to be sure and use 6 point sockets (flank drive) if you have them. I would think that they're either M15 if they're OE or possibly M13. The later '94+ I believe are M13. If your 9/16 spins go to M13, if it doesn't fit go to the M15.
Last edited by WVZR-1; Sep 24, 2013 at 03:25 PM.
Race Director
Joined: Apr 2000
Posts: 15,344
Likes: 4,009
From: Texas
Nope, no one has ever taken them off before. 21 years after the LT1 was introduced, we're still waiting for the first success story 
Theoretically speaking...since it's never been done...extensions, a deep-well socket, and a universal or two works wonders for snaking things around where they need to go. It's also been theorized that removing the manifold/cat as an assembly from below works wonders. Of course having the oil filter removed on the driver's side and the starter removed on the passenger side helps with clearance. Again, just theoretically.
Theoretically speaking...since it's never been done...extensions, a deep-well socket, and a universal or two works wonders for snaking things around where they need to go. It's also been theorized that removing the manifold/cat as an assembly from below works wonders. Of course having the oil filter removed on the driver's side and the starter removed on the passenger side helps with clearance. Again, just theoretically.
Safety Car
Joined: Jun 2003
Posts: 4,250
Likes: 656
From: San Diego Ca
Been there and done that but years ago. I don't think there was anything I got from above. It is really nice to have a lift.
I do recall that the real problem is a passenger side bolt as described above. Wish I could remember exactly how I got to it but it happened.
I do recall that the real problem is a passenger side bolt as described above. Wish I could remember exactly how I got to it but it happened.
Last edited by pkincy; Sep 25, 2013 at 12:06 AM.
Le Mans Master
Joined: Dec 2006
Posts: 5,139
Likes: 482
From: H-Town Texas
3rd Gear
Joined: Oct 2016
Posts: 3
Likes: 0
cat removal
I'm trying to remove the stock exhaust manifold and catalytic converter. The bolts that connect the exhaust manifold to the exhaust pipe (about 12 inches upstream of the catalytic converter) are difficult to reach. They are a 9/16 bolt that is about 3 inches long. The frame and other components make it difficult to reach up to.
Has anyone removed this before? If so, how did you get it off?
Has anyone removed this before? If so, how did you get it off?
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