Insulate the Catalytic Converter?

[imzjustplayin]

Is there any reason why one would not put insulation around the catalytic converter and exhaust? I mean in a high performance engine, you wouldn't want to do that in order to have it dissipate heat but in a lower displacement motor (under 2 litres), is there any risk in having the catalytic converter run hotter? I mean cats run better when they're hot so I'd figure that the hotter the better. What is the temperature limit of a catalytic converter?

[kamesama980]

cause from the factory they're set up to run pretty close to the ideal temp. wrap it up and you might overheat it. I'd wrap up to the cat but not the cat itself.

FYI high end engines DO wrap them to keep from melting everything around them. a side benefit is it keeps gas temps up to keep exhaust velocity up for more power. often they don't have cats tho.

The other downside is that they can retain water, holding it against the pipe. usually those aftermarket engines don't wrap the exhaust outside the engine bay and aren't driven in bad weather.

[VetteOwner]

yea i know ppl who wrapped thier headers and they rusted out in a year or so...

[101mpg]

Uh, fire? Probably enough reason not to insulate it. All you'd do would be trap more heat in there, and this would rust the pipes plus increase the chance of fire.

[Wyldesoul]

Chance of fire? What would catch on fire?

[JanGeo]

I have a header heat shield and it come out the back end of the engine between the engine and the fire wall not in front to get cooling air like most engine setups. I added some aluminum foil onto the heat shield which was full of holes to block more heat from the fire wall and PS Pump right near the header and to keep the exhaust hotter since I really don't run high power levels at all. Since the foil has plenty of air flow on both sides it doesn't interfere with water evaporation from the header or make contact with the actual pipes. I didn't wrap the cat at all since at some point an inspection will need to be done on it and I don't want to spook the guys at the garage.

[unstable bob]

Originally Posted by Biffmeistro

Chance of fire? What would catch on fire?

I know a guy who wrapped up the headers on a late model Camero, had some oil leak out from his valve covers and get on the wrap, and the car went up like a Roman candle.

[dkjones96]

Originally Posted by VetteOwner

yea i know ppl who wrapped thier headers and they rusted out in a year or so...

Back home I knew a bunch of people that happened to. Now though, in the desert, even regular steel exhaust systems don't rust much. It took my new rotors a good few months to rust on the areas that the pads didn't touch. Then again, it took a few months for us to actually get rain, so yeah lol

[brucepick]

Originally Posted by unstable bob

I know a guy who wrapped up the headers on a late model Camero, had some oil leak out from his valve covers and get on the wrap, and the car went up like a Roman candle.

If he hadn't wrapped the headers the oil would have gotten on the headers - probably with the same result? Unless maybe the thermo wrap soaked up oil like a sponge which might have been worse than what happens when it falls directly on the header.

That said, I suspect the designers have put enough thought and testing into the cats. Putting a grill block in front of one that's up front might be good in winter. But I wouldn't be comfortable wrapping one for all the reasons already given in this thread.

[shatto]

Originally Posted by Biffmeistro

Chance of fire? What would catch on fire?

What could catch on fire?

Just funning you.
Most fires start in the engine room.