There's been much debate regarding the difference in the sound between a high flow cat and a test pipe. So here it is:

RT high flow
http://yfrog.us/2gcatz

Test pipe
http://yfrog.us/2otestpipez

Keep in mind this is with IHE. Test pipe is indeed raspier. In cab drone increased a bit, but not awful. I would keep the test pipe over the cat for a better flowing system any day. I guess it's a matter of preferance really. Hope this helps!!

 

thanks for posting..i will post a vid of my hs headers and cattman c/b with a cat on a dyno..i dont care for a test pipe on an NA car

 

like hotshot said, test pipe makes no difference it only increases sound, thats it... RT or magnaflow high flow cat is more than enough, for whatever bolt on you have

 

is that the 3" cattman?

thanks for the side by side video

 

this is something i'll be doing on winter time..

 

Like the high flow cat sound

 

It felt like the RT was a little restrictive. With the testpipe, it felt like the exhaust flows better. I am not the only one in this forum that has posted about faster acceleration with test pipe. Call it psychological. I don't care.
Plus, it's a third of the cost.

2 1/2 for now. 3" coming soon

 

Thanks for sharing; I plan to replace my cat with a magnaflow 3" resonator and then mandrel bent 3" piping to a vibrant 1047 muffler.

 

i feel what your saying, i really do, its a mind thing though i remember when i had a straight pipe on my 4th gen from lss exhaust, i dont know how to explain the feeling, but their is really no difference, i think its the sound why most ppl think that... ask jaypee and his 12 sec 5.5 (has high flow cat)

 

I've read somewhere that cats with ceramic internals can actually rob horsepower. I wish I remembered where.
Is Jaypee N/A?

 

yea, go check out the 1/4 section... care to post where u read that?

 

Like I said, I wish I remembered. It was long ago. I will try to find it.

 

oh... o.k cool

 

w/ test pipe max sound like a 350z

 

hahahahaha its crazy how the G35 350Z sounds always come up... a maxima does not sound like neither

 

Raspier IMO

 

yes

 

YES

 

You can call it rasp, but I think it sounds twice as good. It sounds like it has *****. Too smooth and there's no oscillation of the tone. It just sounds like one big drone.

 

Cant find where I read that.
But I will tell you one thing. My trap speeds are 3-4 MPH faster without high flow cat.

 

hmm... thats arugable but o.k

 

I know it sounds crazy, but I ran the track yesterday the same way I always do and my trap speeds were much faster.
I plan to dyno once I get the EU and 3" exhaust installed. I will do one run with and w/o high flow cat.

 

why not do the F-spec ECU upgrade???

 

I already have it.
As you know TS is a cookie cutter tune. I honestly can;t wait to street tune it the way I want it. IMO, the only benefit of TS is that the alter cam timing.

 

use that along with a SAFC.... what were your 1/4 times

 

Don't like the SAFCII. I would like to data log.
Track times were horrendous. Don't care to comment. I can't seem to get traction off the line. By the time I hook up in 2nd gear, I've already lost a couple of seconds Street tires suck!!

 

o.kaaaaaay!!! get a VAFC2 and a wideband o2

 

I can believe that. Thanks for the info.

 

Drag radials?

 

Datalog with laptop. I have wideband

 

Hell no.. I wish. Freakin street tires

 

I meant, invest in some.

 

That's probably true if you are comparing a test pipe to a brand new high flow cat. However, most of us have enough mileage that our OEM cats have enough gunk built up in them to reduce performance.

 

Oh yeah
And some lightweight wheels. My touring wheels only weigh like 28 lbs a
piece

 

Datalog with AFC and wideband huh? That's interesting.

 

i can agree about the OEM cat, but do you think its the same for the random technology high flow or magnaflow high flow cat convertor???... just a question, idk

 

VOLK TE-37s, Rota Slipstreams or Kosei K1's. All very light weight and good looking IMO.

 

rota grids too... volk te knockoffs

 

I think it would be. Actually, OEM cats flow much better than aftermarket "high flow"

 

So much better without the cats, you should hear my car. I have had everyone from subie owners to hot roders tell me my **** sounds mean and it shocked um. The cam and no cat made all the difference. No cat FTW!!! Im registered out of county so the car dosen't have to go through emissions. No cats, just a resonator and megan muffler.