Anyone know the expected difference in power from a resonated test pipe vs. a high flow cat. I would imagine the test pipe would flow better= more power gain but what do you guys think/know?

I'd actually be more worried if you have to pass emissions with your car or not. I don't know what it is like in other states from CO, but I'm exempt. Test pipe will be louder too.

I do have to pass emissions. My buddy has a lift so once a year i could just swap the test pipe out with my cat. No biggie there.

With the high flow cat, technically you'll still be legal. With the test pipe you can achieve high HP without worrying about blowing up your cat.

The high flow cat will keep you in theoretically in the legal side. But in some states or hard inspection you will most likely fail.
The test pipe is loud but you get more gain and steady whp.
The resonated test pipe a slightly less whp gain, but still steady whp + quieter or even quieter then some high flow cat.

Test Pipe = Bad Smell when not moving, loud, and massively illegal. All for maybe 5whp over a highflow cat. Not worth it IMO.

Test Pipe = Bad Smell when not moving, loud, and massively illegal. All for maybe 5whp over a highflow cat. Not worth it IMO.
what test pipe have you run? mine dosent stink at all. while it may be illegal, i would say go test pipe FTW!

Test Pipe = Bad Smell when not moving, loud, and massively illegal. All for maybe 5whp over a highflow cat. Not worth it IMO.

that high flow cat which is suffers only 5 whp versus test pipe in the Evo is also massively illegal for public road.
Also when its really heats up will rubs even more whp. Not to mention the smell.
so the test pipe or the resonated test pipe is a winner ,if you go illegal anyway.
Plus its cheaper then the high flow cat. So why spend extra, for less and illegal on public road?
Now if you run some race events, which is requires cat, then make sense to have a high flow cat. And basically that is a main purpose for the high flow cat. /Like Red Line Time Attack street class, which is requires a cat/

that high flow cat which is suffers only 5 whp versus test pipe in the Evo is also massively illegal for public road.
Also when its really heats up will rubs even more whp. Not to mention the smell.
so the test pipe or the resonated test pipe is a winner ,if you go illegal anyway.
Plus its cheaper then the high flow cat. So why spend extra, for less and illegal on public road?
Now if you run some race events, which is requires cat, then make sense to have a high flow cat. And basically that is a main purpose for the high flow cat. /Like Red Line Time Attack street class, which is requires a cat/


LOL, since when are high flow cats illegal? Maybe if you are buying some cheap version, but if properly made it will pass both visual and sniffer test.

what test pipe have you run? mine dosent stink at all. while it may be illegal, i would say go test pipe FTW!

Why does it matter which one? They are all just sections of metal pipes.

And sit in a car in traffic with a test pipe for awhile and you will notice some fumes coming into the cabin.

LOL, since when are high flow cats illegal? Maybe if you are buying some cheap version, but if properly made it will pass both visual and sniffer test.

well, i said wich are 5 whp less only then test pipes.... if it wasn't clear for you.
Those are which will pass california and so inspections, are not 5 whp less restrictive vs test pipes. Most likely 10 or above. Untill they heat up.
Then when they really heat up, they will be over 15. But if you know any high flow cat, wich is when its fully heated up and only 5 whp less then a test pipe and pass all the inspections, please link me to it.
I'll be buy one in a heart beat.:rock:

PS you will be surprised, how many High flow cat is illegal on public road, if you are following the rules./ like in California, or NJ. :) /
Also as your WHP numbers are getting bigger the difference between test pipe vs high flow cat will be greater too.

Meh, i dont consider Cali or NJ real states. :p

And yes, i can almost guarantee you that a 3" high flow cat wont result in anything more than 5whp loss vs a test pipe.

And the knowledge that you are helping to save the environment and avoid thousands in EPA fees if you got caught are priceless. :P

And here is a 3" cat for $90 bucks... even cheaper than some test pipes. :)

http://www.kteller.biz/prodtype.asp?cookiecheck=yes&PT_ID=134&strPageHistory=cat

get a cheap pipe and get cheap results

Meh, i dont consider Cali or NJ real states. :p

And yes, i can almost guarantee you that a 3" high flow cat wont result in anything more than 5whp loss vs a test pipe.

And the knowledge that you are helping to save the environment and avoid thousands in EPA fees if you got caught are priceless. :P

And here is a 3" cat for $90 bucks... even cheaper than some test pipes. :)

http://www.kteller.biz/prodtype.asp?cookiecheck=yes&PT_ID=134&strPageHistory=cat

put that cat on your car run it on the dyno when it is reach the operating tempeture, then swap it to the test pipe , you will be hell of surprised :bowlol:
This cat is at least 15 whp down to test pipe. Since at least 14 whp down his bigger brother the 100 cell metallic racing cat.
not to mention it will fail in cal or jersey so it is not legal for at least 50 states.
the most so far you can get out from high flow cat is the 100 cell metallic racing cat. This is not even metallic , still ceramic.
The 100 cell metallic cat/ which is absolutely NOT street legal/ is still trailing the test pipe or the resoneted test pipe over 5 whp./dyno proven/
Now most cat is over 300 cel per square inch what you can buy.
If you really want a good not restrictive high flow cat then you need this one:
http://forums.evolutionm.net/showthread.php?t=330262

BUT remember it is not street legal , so pointless for dd. Only if you are a racer and you definitely need a cat for your class.

i use a test pipe all the time. sounds great and i dont get fucked with

... while it may be illegal, "MAY" be illegal? What country are you from?

i know that its illegal. read it again

DOH!