Kenpo_S2000

How much of a difference in sound and performance is there between a resonated test pipe and non. I have a resonated test pipe but was hoping to get the berk or similiar from someone looking to sell one on the board. Is it worth it to go with the straight pipe and ditch the resonated version?

neveronlines2k

I dont think it will matter to be honost, maybe a little soundwise. I went back to the stock cat after dyno'ing my car with the test pipe and with the cat due to a loss in TQ and HP with the TP installed . It did sound better with the Test pipe though.

note: I did not have fuel tuning of anykind and I beleive OBD2 was the reason for the loss in power. If you are using a VAFC or other tuning device disregard the above statement.

Kenpo_S2000

I am not running the VAFC my mods are listed in the sig.

neveronlines2k

If there are no future plans to add some type of tuning device, than I dont think you will gain much if anything (you may even lose some HP and TQ like I did). Since your car is an AP1 and mine is an AP2 I dont know if the outcome will be the same. Remember the OE cat is a high flow unit and you could always dyno it to see the outcome with testpipe and then with the cat.

If you could that would be great cuz I would love to see the results. If you do this and it is possible for you. Put the test pipe on first and drive the car around for a while maybe a week or a month (depending on how often you drive) than baseline the car 2-3 passes on the dyno should be good. Then take the test pipe off and put the cat on and do a couple passes again and compare the results. If you cant do it no worries . I am just wondering if my car is a freak of nature or what .

The reason I say to do it that way is to give the car a chance to see the difference from the test pipe. My thinking is that the obdII ecu detects the changes in airflow/exhaust temps (or something) and changes the timing/fuel and thats what causes the loss in power. With tuning I am almost positive you would gain power from a test pipe as a lot of other members on the board have.

See the NA thread in the JDM forum.

Good Luck

Kenpo_S2000

Thanks I will check out the forum. As for the dyno the closest one is probably a good 3 hour or more away. I will do some more searching, some day I would like to get a VAFC but again I will have to make the trip to the dyno. That is probably the only thing holding me back right now.

neveronlines2k

Ya I hear that (about the dyno's that can make it a pain).

Its just hard to say power wise what is the better choice because I would have bet money my car made more power with the test pipe than with the cat (car felt quicker and sounded better), but the dyno did not reflect that .

Boofster

There is no reason you would lose performance by removing something that essentially obstructs your airflow path. Unless there is something going funny with the A/F settings from the o2's in the ECU.

PBE Gummi Bear

i preferred the sound of my exhaust on my integra with the cat on there over the test pipe. the test pipe makes it seem too raspy. ive never tried a resonated pipe, but you shouldnt feel any loss.

neveronlines2k

[QUOTE=Boofster,May 11 2007, 09:55 AM] There is no reason you would lose performance by removing something that essentially obstructs your airflow path.

__redruM

I know that's the conventional wisdom here, but maybe if the ECU is tuned to expect a certain amount of Exhaust Backpresure, and it isn't there, then the a/f mixture will be off. This would explain the dyno results...