high flow cats? reccomendations?

[BlazinUP]

i allready installed a dynomax ss high flow exhaust......
was thinking about a hf cat.
worth it....? will it give me a louder tone?
and should i go hollow,,,or just higher flow?

[dmbrisket 51]

emissions an issue?

[BlazinUP]

emissions in my area isnt an issue.......
but if a hollow cat isnt gonna make it sound MUCH better than a h/f..then i would stick with teh h/f.
plus i dont wanna loose so much backpressure...that i could eventually damage my engine.

[dmbrisket 51]

if you have the hf cat keep it, you compensate for removing the cat with smaller pipes so you dont damage anything, but overall removal of a hi flow for a steel pipe wont make much difference

[BlazerLT]

High flow cats do seem to make a difference seeing the stock one is rather large and is used as a resonator in our exhaust system to take a little of the grumble out.

I installed one and man, it sounds nice. Especially at higher rpms.

But only replace it if your is having a problem or is broken. I only replaced mine because one the the internal biscuits came loose and was rattling.

[chcknugget]

What does the rattling sound like? It seems like some trucks have this hissing sound like a boiling coffee pot. I don't really know how to describe it- it's sorta like the electric motor sound the rear window sprayer makes on my jimmy. Is that related to the cat?

[BlazerLT]

Hissing sound should be the fuel pump.

The rattling noise is a metallic tight rattle under the truck.