Fairly uneducated on the exhaust but ive searched and found hit and miss answers nothing direct. First i considered replacing the cat with a test pipe and that seems like a pain for emissions testing changing it out ect and CEL lights which drive me nuts. Then theres perrins (im sure there are plenty more) Catalyst replacement which i believe is a high flow cat but no indication anywhere that it does anything performance wise just as stated a replacement? Can anyone shed some light? Thanks

 

don't know about the strictness of emmissions testing in VA but in "green" states that have adopted CA emmissions ANY aftermarket cat is illegal. Perrin is a "HFC" but if your gonna be in the grey area just run a test pipe with the spacer under the sensor. I had the rear O2 disabled with my tune but the spacer works good also, no cel.

 

I had considered that but i was tryin to stay on the safe side with a cat but its hard when a test pipe is cheaper and better gains. Thanks for the info.

 

Perrin is a metal cat with a 300 cell unit.

MIL.SPEC makes a 100 cell cat.

Testpipe is the most horsepower, but my opinion is that it's environmentally irresponsible...especially with high flowing cats that will clean the exhaust while making a lot of power.

 

I just got my emmission done with test pipe, no problems. I think as long as there is no cel you will be fine

 

BS you lie!!!!!!!!!

 

Even HFC's can throw CELs. I have the Vishnu turbo-back system with a HFC and I would get CEL from the cat. I still had to use a spacer.

 

Perrin claims it's a 200 cell cat:

http://www.perrinperformance.com/pro...gory=6&model=3

Either way, it won't flow as much as a 100 cell.

 

Theres always the WORKS stealthworks cat. They basically take the guts from your stock cat and adapt it into 3" piping so it flows more volume, but still has stock emissions. Thats the route i think i'm taking.

 

If your in a state with no emissions testing it doesn't matter what you have hooked up unless you have a CEL or if the inspector cares to check . Some states do emissions on OBD2 cars.

 

I had one and its definatley a 200 cell cat. I had it for about 6 months and it failed on me. After a road course track day , my car would build boost very slowly and would not boost more than 15 psi.It turned out the honeycomb in the cat was loose and rattling around.

 

I have a UR cat. and so far it has worked fine...I wish someone would make a true 3" 100 cell cat. that was plug-n-play for our cars....(The milspec one requires fabrication unless they have added an option...)

 

A testpipe would be your best choice, especially since there are so many effective ways to disable the rear o2 sensor CEL. If you do decide to get a HFC instead though the Mil.Spec 100-cell would be your best choice.

 

Thanks guys for all the great info, really appreciate it. Think im going with Mil Spec because they do indeed have a bolt on cat now.

 

Really ??? Is there a website with pictures and prices ? Last I heard they just sold the actual cat that needed to be welded to more pipe and then flanges welded on the ends...