Single Cat

[KillerSix]

I am considering replacing both stock cats with a 2.5in high flow rated for an engine of 5.9L. I believe it would unleash more power but i haven't read on it so what do you guys think?
........ sorry, realised its the wrong section, my bad.

 

[kevinspann]

Uhhh, neat I guess. Where are you going to fit it?

 

[KillerSix]

most likely a bit further back where the two cats would join into the Y and have a custom Y from the manifold to the cat.... trying to stay emmissions legal but if its not really gonna help on performance i will probably just straight pipe it.

 

[whiteman_01]

I had this done a number of years back. My exhaust guy made one for myself, and another for my brother. He used a high flow cat for a dodge 360. They performed quite well, Both are still in use, and im thinking we paid 250 for both of them.

 

[KillerSix]

Alright, sounds good. Thanks for the info. I have an offer to get it done for 150.

 

[LOUDSHO92]

A 2.5" cat would be a restriction over 2 2" cats. You would have to go 3" to get larger. Also I am not sre what the emissions laws are in Texas but if you did this in CA it would be illegal. Just something to consider.

We do offer a high flow y-pipe that is all stainless: SHO Source

 

[rubydist]

yeah, the law says that if the vehicle is certified w/ 2 cats, you cannot replace them with a single cat, even if the single cat has the capability of doing the job. so, if you are in a state where they do visual inspections on the emissions equipt, you are likely to have a problem.

 

[operdot]

Also be careful how far back you place the cat. Catolytic converts only work above a certain temperature. The further back the are placed the lower the exhaust gas temperature which yields the cat useless.

Like if you put it as your muffler it won't do anything.

 

[KillerSix]

Thanks for the information guys.... saved me some money and time. Its lookin like i just might as well straight pipe it. If i'm gonna break the law, might as well go all the way.