Test Pipes

[Racer 007]

I am debating on whether to get a test pipe or not. I do know that it makes your exhaust sound a lot tougher but what does it really do?

I have heard that it will decrease your bottom end torque quite a bit but increase your top end. Not good I suppose for stoplight to stoplight or track use.

Does anybody have any opinions on this?

Also, if I just gut my cat, will that provide enough back pressure or will it perform just like a test pipe?

[92es]

From my research on 3Si, I gleaned that the test pipe has a few functions. 1st, you can easily replace your intact cat for emissions tests. 2nd, it is straight instead of chambered like the cat so exhaust flow is quicker, therefore more HP. I'm not sure about the significance of backpressure a la gutting the cat for the torque issue.

my .02

[Racer 007]

Hmmmm, it just seems that I would probably rather have low end torque rather than a loud exhaust.

[detpac]

It does get louder. Sounds more throaty.

[Racer 007]

But I believe you can also get that sound from a gutted cat. It's the back pressure question again here. Will a gutted cat provide the necessary backpressure needed to maintain low end torque and yet have the growly sound also?

[99VR4SupraHunter]

Don't go messin around with a test pipe or gutting your cat. Just keep it like it is.

[Racer 007]

I have now installed the test pipe and I can attest that the thing is at least 10x louder than before. I let somebody else drive it and they were over 8 blocks away and it still sounded like it was around the corner. Dayum, my car sounded so freaken loud.

I was at a parking garage yesterday and I revved it up and it seemed like I chirped every cars alarm on the level I was on. Major difference in sound.

I haven't punched it yet to see if I can feel any gains as it has been raining pretty heavily. I also put in a DN intake pipe to replace the rubber one that connects the MAS to the TB. I bet that helps throat out the sound also.

[Racer 007]

Punched it now a few times and all I can say is "LOUDER THAN SHIT". My wife can hear me coming home about a 1/3 of a mile away. I like it.:D