Cats Melting And Blocking Up

[VXCLUBBYLS1]

my last car was a vl calais turbo which was pretty heavily modified over 25000 spent on it. the thing is i had a magic cat on it and it melted over and blocked the exhaust stopping me fom makin boost just wanna know has anyone else came across this

[JezzaB]

my last car was a vl calais turbo which was pretty heavily modified over 25000 spent on it. the thing is i had a magic cat on it and it melted over and blocked the exhaust stopping me fom makin boost just wanna know has anyone else came across this

Throw more fuel in to cool them down? Leaner and running hotter?

Stock LSX PCMs do this as standard as Cat Protection.

[Lokky]

I thought that cats got hot when the engine was running too rich.

The cats work by breaking down fuel and the nitrogen dioxide etc in the exhaust and give off heat as part of the breakdown process.

[JezzaB]

I thought that cats got hot when the engine was running too rich.

The cats work by breaking down fuel and the nitrogen dioxide etc in the exhaust and give off heat as part of the breakdown process.

I just did a bit more research on this and you are right. Thanks for making me look it up and have a better understanding :cheers:

[iamhappy46]

There are a few reasons why a cat can melt, running too lean can cause excessive heat and melt the substrate(which is most common on ceramic cats) but you can also run them too rich, the excess fuel liqufies inside the cat(depending on position) and when it gets lean enough again or you have a small backfire, the fuel ignites inside the cat and melts the cat as well.

There is also cases of where people have driven through a car wash and the water spray under the car, has hit the stainless steel casing of the cat and caused it to shrink while the substrate was still hot, cracked the substrate and twisted inside the cat body to block off flow out of the outlet.

Lots of reasons and it can be a pain finding out why yours failed.