hey i just gutted out the cat the other day and it kind of sounds shitty but feels a little quicker if i got a high flow cat that is 3 inch would that sound pretty good or would it osund about the same

 

i regular cat its for restriction purposes so yo can pass d emmisions if there is any in ur state. a high flow cat its just basically the same as running straight pipes, wont pass emmisions. if your turbo your prob, wana run straight pipes

 

are u sure? why would someone develop and make a high flow cat if you won't pass emission. im pretty sure with a brand name high flow cat u will pass emission as with a test pipe you will not.

 

im like 99% sure, was going to buy one for my teg but was told by differnt shops that by the time that i neede to take my car to emmisions i needed to be replaced with stock. also if you look at one closely you will see straigth tru, compare to the retrictions the stock one has. any1 else wana input on this?

 

you will not pass emissions with high flow cat nor a test pipe. they test emissions from the gases coming out of the muffler.. with test pipe and high flow cat, compared to a stock cat.. there is no honeycomb material in either to break down hazardous gasses as a stock cat would. you can see considerable gains with high flow cats etc though. so just put one on and when its time to inspect, put the stock back on. it wont take long

 

as you know the cats have a honeycomb type material all in it. you take a look at the stock the honeycomb are very small. in high flow cats the honeycombs are alot bigger than stock allowing more airflow. from what i understand the honeycombs are made of some type of material to transform harmful pollutant into harmless compound so i believe the high flow cats will do the same.
Independent testing by engine builders, racers, and automotive magazines has repeatedly proven the superiority of the Random Technology SuperStainless design.

This design, which meets Federal EPA and California ARB requirements, enables virtually any vehicle with a properly tuned engine to meet emissions standards with little, if any power loss (compared to an exhaust with no catalytic converter).


Modified by shyboi4u at 2:51 AM 10/21/2005

 

It would sound about the same.

 

high flow cats do not sound bad
I passed the SMOG test with a high flow cat in Cali so you should be able to pass anywhere.

 

will the flanges on a 2.5 test pipe or HF cat, bolt up to a 3 inch downpipe??

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by LSRracing95 &raquo;</TD></TR><TR><TD CLASS="quote">you will not pass emissions with high flow cat nor a test pipe. they test emissions from the gases coming out of the muffler.. with test pipe and high flow cat, compared to a stock cat.. there is no honeycomb material in either to break down hazardous gasses as a stock cat would. you can see considerable gains with high flow cats etc though. so just put one on and when its time to inspect, put the stock back on. it wont take long</TD></TR></TABLE>

No, actual high flow cats (made by companies like Catco, Random Technologies, or Carsound) do actually function as catalytic converters (many are even CARB exempt), so you can pass emissions with them in. Hit up SMSP to make you a custom one. The 'high flow cats' that are sold on ebay for cheap tend to be resonators with an o2 sensor bung in them, and are basically the equivalent of a nicer sounding straight pipe. Those would not work for emissions, but a REAL high flow cat would.

 

What about durability, does high flow from Catco or Carsound last shorter than stock or non-highflow?

 

I passed with my highflow cat here in CA for my emissions test

 

Some people say the aftermarket high flow cats won't last as long as an OEM cat, but those same companies make some non high flow cats, with similar workmanship I assume. Look for some threads by 'SMSP', he did some high flow cat comparisons, I think he used to use Carsound and ended up going with a lesser known brand because he felt it was better quality. I think that thread was a long time ago, so look in the archives.

 

yeah i thought i was right about it. that would be stupid buying a high flo cat and failing emissions, you might as well bought a test pipe.