While trying to sleep last night, i was thinking about the K20 motor and about how Honda flipped the Intake and Exhaust Manifold. I heard one reason for them doing this was to have that cat closer to the engine so the cat would run hotter and burn more efficiently.
Im just wondering, if it might be a good idea to wrap your cat in thermal header wrap to keep it hotter to run more efficiently? ..or would it just melt it???
Thanks for reading!
i searched and found these interesting threads...
https://honda-tech.com/zerothread?id=582689
https://honda-tech.com/zerothread?id=215807

 

good point

 

Interesting thought, I'm going to do some research.

 

My understanding is that moving the cat closer is to get it hot faster, not hotter all the time. With the efficiency of new cars now, the cold start produces more emissions than miles of running warm. Most cars are tuned to run rich at WOT to keep the cat from getting too hot. If they get too hot, they melt internally and then clog up the exhaust flow. My old 86 RX7 had a warning sensor for overheating the cat, just in case. Of course rotaries produce exhaust temps that piston engines would melt at.

It takes a certain minimum temp for the cat to start the chemical reaction that neutralizes the emissions but I have forgotten what it is. The temp 700degF rings a bell, but don't quote me on that. I think the chemical reaction will get better with more temp, but the structure that holds the catalytic material will fail above a certain temp. I'm on the side of don't wrap it.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Mohudsolo &raquo;</TD></TR><TR><TD CLASS="quote">My understanding is that moving the cat closer is to get it hot faster, not hotter all the time. With the efficiency of new cars now, the cold start produces more emissions than miles of running warm.</TD></TR></TABLE>Yes. Coming up to proper temperature FASTER is one thing, getting too hot is something completely different. I wouldn't wrap it.


<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Mohudsolo &raquo;</TD></TR><TR><TD CLASS="quote">Most cars are tuned to run rich at WOT to keep the cat from getting too hot. If they get too hot, they melt internally and then clog up the exhaust flow. My old 86 RX7 had a warning sensor for overheating the cat, just in case. Of course rotaries produce exhaust temps that piston engines would melt at.</TD></TR></TABLE>I thought running rich would overheat the cat. It's done at WOT to lower combustion-chamber temperatures, & the cat has to tolerate it for short periods of time. I heard somewhere that ALL cars in Japan are required to have a hot-catalyst warning. So Mazda decides to keep that sensor & warning in USA cars, while most others only install that in JDM cars.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Mohudsolo &raquo;</TD></TR><TR><TD CLASS="quote">It takes a certain minimum temp for the cat to start the chemical reaction that neutralizes the emissions but I have forgotten what it is. The temp 700degF rings a bell, but don't quote me on that. I think the chemical reaction will get better with more temp, but the structure that holds the catalytic material will fail above a certain temp. I'm on the side of don't wrap it.</TD></TR></TABLE>Yes, but I don't remember the exact temperature either.

 

lol..it took just over 3 months to get a reply!

haha..thanks everyone!

 

I Wouldnt think it would melt it.
Great idea though