Reducing Exhaust Heat (Under Tub, Not Inside)

SSTJ

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Inside the tub, I already have sound dampening materials and carpet. I'd rather not add anything to that.

But it still gets hot to the touch under the passenger seat, which I think is right above the catalytic converter. This is also where I mount my Ham radio.

Has anyone had any luck with anything applied under the tub, like an improved heat shield, or some kind of wrap?

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Edit: Reading this and this and this and this, it sounds like the options are additional heat shield, exhaust wrap (with concerns about trapping moisture) and ceramic coating (sounds pricey).

Edit: I think I'll see if my new catalytic converter runs any cooler than the old one. If not, I'll try some DEI tunnel shield.

Edit: Learned today that my 97 SE has an impressive set of heat shields on it. The first runs the whole length of the catalytic converter and muffler. The second is in the rear passenger corner, where the tail pipe bends over the rear axle. The third is on the muffler itself. Pics of each are below.

Above CC and Muffler
Above Tail Pipe
On Muffler
IMG_8222.jpeg

IMG_8220.jpeg
IMG_8219.jpeg

Screenshot 2023-08-30 at 9.52.56 PM.jpg
 
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The heat shield I'm referring to is only between the main catalytic converter and floor.

Hi @Jerry Bransford

Interesting. Maybe it's a 97 thing, or a 2.5 thing, but mine definitely runs the full length of the catalytic converter and the muffler.

Pic attached. Is this what you had in mind? (Sorry not better pic.)


IMG_8182.jpeg
 
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Bump. I'll be working on the exhaust next weekend, so that'd probably be a good time to do something, if anything.
 
Bump! Or maybe my OEM heat shield is as good as it's going to get?

I also think that my catalytic converter is shot. So maybe the replacement will run a bit cooler anyway?
 
Bump! Or maybe my OEM heat shield is as good as it's going to get?

I also think that my catalytic converter is shot. So maybe the replacement will run a bit cooler anyway?

If you have to replace the cat you might think about getting something like what I'm using.

https://www.magnaflow.com/products/091-1016-catalytic-converter-federal-universal

It would have to be welded in but smaller than stock. Of course this only works if you don't have to be emission tested.

Also I'd check around and see if you have a local shop that does ceramic coating as it really wasn't that expensive.

Your other option would be to pull your tub & spray the underneath with Lizard Skin.
 
Bump! Or maybe my OEM heat shield is as good as it's going to get?

I also think that my catalytic converter is shot. So maybe the replacement will run a bit cooler anyway?

Have you confirmed that your third cat is actually bad?

Btw, you could skip the third cat if your emissions don’t involve a visual inspection. That’s what I did since AZ only cares about the o2s reporting that the precats work. I may throw on a bottle style resonator by Vibrant later.
 
Have you confirmed that your third cat is actually bad?

Btw, you could skip the third cat if your emissions don’t involve a visual inspection. That’s what I did since AZ only cares about the o2s reporting that the precats work. I may throw on a bottle style resonator by Vibrant later.

I only have one cat on my 2.5. I'm not sure it's bad, but it's at 100k miles and 25 years and I found a cheap replacement so I'm going to swap it out soon anyway.
 
I only have one cat on my 2.5. I'm not sure it's bad, but it's at 100k miles and 25 years and I found a cheap replacement so I'm going to swap it out soon anyway.

Ahh thanks for the education.

Btw, you can scope the Cat from the tailpipe to confirm the condition if you want to do so before having the part changed.

My understanding is that a cat that's dislodged or melted enough to plug things up many times will hurt your mpg and/or limit your ability to move more air (go approximately 50+mph).

Consider that you might be running too rich which I believe could make the cat get hotter than it should (and could melt a cat). Just mentioning that because even if you swap the part, you don't want to hurt the next part.

With that said, cats should get pretty darn hot so you can always run a heat shield on the cat if you have the room.
 
Thanks. Ok, will keep all that in mind. And yes, I'm liking the heat shields recommended by @macleanflood above, so may try one of those in addition to the OEM heat shield.
 
Ahh thanks for the education.

Btw, you can scope the Cat from the tailpipe to confirm the condition if you want to do so before having the part changed.

My understanding is that a cat that's dislodged or melted enough to plug things up many times will hurt your mpg and/or limit your ability to move more air (go approximately 50+mph).

Consider that you might be running too rich which I believe could make the cat get hotter than it should (and could melt a cat). Just mentioning that because even if you swap the part, you don't want to hurt the next part.

With that said, cats should get pretty darn hot so you can always run a heat shield on the cat if you have the room.

Broom handle really fixes the clogged cats good! Just ram it through A few times!
 
Broom handle really fixes the clogged cats good! Just ram it through A few times!

I drove my rig with no cats for a short-term solution —> and it was absolutely miserable!!! The only thing worse was driving with my new headers not attached to the turbo plumbing (needed welded). 0/10 would not recommend lol.
 
I drove my rig with no cats for a short-term solution —> and it was absolutely miserable!!! The only thing worse was driving with my new headers not attached to the turbo plumbing (needed welded). 0/10 would not recommend lol.

I didn’t say no muffler, just hollow 🐈‍⬛