Will a 3" high flow cat fit on a completely stock exhaust? I tired searching but couldnt come up with a definitive answer.

 

It will probably fit but I think there's no point because the factory exhaust isn't a full 3''.

 

Yes, depending on which one you get. They all just bolt up to each other easily - it's a flange thing. However, it would be a big waste of money, since it won't make power and costs a lot. If you put in a test pipe, that WILL make power for very little money without making the exhaust loud.

 

Thanks guys i was just figuring because its sunday and i have not much to do, and i do have a HFC coming in. I am going to be buying a full turbo back in a couple of weeks and i also ordered a UR test pipe so i figured i would try the high flow cat for a little then when i get the TBE i'll throw the ur test pipe on as well

 

Why did you get both? You have no use for the HFC unless you use it with the TBE, and that's just to keep it looking legal and not sounding as loud.

 

and it's highly illegal!

 

Highly? I guess, but no more so than the thousands of other Evos with exhausts.

 

I dont know. I bought it then changed my mine so now i have both

 

Warr -- Please please please.....You know a lot about the DSMs and EVo, but a catalytic converter is designed with a purpose. The 5 - 10 (peak hp) that a cat. may be 'robbing' is nothing for a street car. In fact most drivers could benefit a lot more by improving their torque curves and learning how to properly take apexes.

Cars that run catless stink, hurt the environment, and are illegal. We really need to clean these boards up and stop recommending catless exhausts for street vehicles...It would be really bad if a governement body started raiding shops and imposing huge fines (like was done in Cali. and Vegas not too long ago)...

To answer your question -- Yes the UR HFC will fit the stock exhaust.

Folks -- a HFC will keep your car smog legal, will help the environment, and will eliminate the nasty exhaust smell...Please do us all a favor and keep the exhausts legal. Thanks

 

Well just got back from giving it a whirl, the bolts on the exhaust are way to rusted and are frozen, so I guess i'll have to wait til i can bring it to a shop. Thanks!

 

Nah....lets shutdown Nascar instead. Think of all the pollution we could prevent.

I cant run a cat because it would get damaged by all the leaded gas my car drinks.

Here's a new avatar for you:

On topic:

There is a thread in the drag racing forum where I guy just ran 11s with the stock cat back exhaust.

https://www.evolutionm.net/forums/sh...d.php?t=235538

 

Chris, a HFC is a federal offense just like a test pipe. I have passed emissions before with a test pipe, and I the whole "smell" issue is a big exaggeration. I smell a few fumes now and then, but it's certainly not as bad as you make it sound. 10-15whp is a good bit, and it improves spoolup as well as the torque curve.

 

Emissions laws say that your OBDII readings have to indicate that your cat is fine.

I don't believe 1996+ cars actually "require" a cat. They assume they have it.
That's why there is no visual catalytic converter inspection. If your system says its ok, then it will pass.

 

Ha Ha !! Love the Tree Hugger Avatar!! lol
Can't wait for the full 3" Buschur CBE coming with my stage I.

 

There is no way you would pass inspection without a catalytic converter in VA or CA as they do both visual and test for hydrocarbons....Where did your car pass without a cat ??? Anyway you and I both know that you are not helping my tree hugging cause (lol) and that for street driving you really don't need the 5 - 10 hp....Finally at the track, use the TP, and get make your laps 0.25 sec quicker ....

Jeff -- I love that avatar You the man....