Zeon

iTrader: (1)

I just wanted to give everyone out there a comparison of volumes for these two midpipes when paired with an Agency Power exhaust. Now I'm not going to sit here and claim this is a really scientific test as its not all on the same roads, there is no stock exhaust comparison, etc, but I hope that someone finds it useful.

For testing I used a Radio Shack 33-2055 Digital Sound Level Meter held by me in the front seat pointing towards the back of the car, using A-weighting (see A-Weighting Wikipedia article for explanation). I tried to take at the average dBA for each driving situation I listed below. My car is a 2004 GT with the stock Potenzas, a K&N drop-in air filter with the sound baffles and 1 screen removed, the Axial Flow short shifter, stock header, compared mid-pipes and the Agency Power exhaust. I'm quite sure that all of the sound levels I picked up were from the exhaust note as it is quite overpowering but if you don't believe me I imagine there are others will attest that it is pretty loud.

As for the sound tests I did all of the tests on the drive I take home from work, using cruise control, and took the levels on the same roads in hopes of reducing any differences in road noise volumes.

Agency Power Dual-resonated mid-pipe
~65 dBA @ idle
~74 dBA @ 45 mph
~85 dBA @ 70 mph
~88 dBA @ 75 mph
~90 dBA @ cruise control accelerating around 4k rpm (like a tick up on the CC speed)

~88 dBA @ 7,000 RPM engine rev
~96 dBA maximum volume

ExoticSpeed Cat-pipe
~62 dBA @ idle
~72 dBA @ 45 mph
~80 dBA @ 70 mph
~82 dBA @ 75 mph
~90 dbA with cruise control accelerating around 4k rpm (like a tick up on the CC speed)

~88 dBA @ 7,000 RPM engine rev
~94 dBA maximum volume

I was hoping for more noise reduction, but maybe the AP exhaust is a larger part of the equation than I had originally thought. I took a ride in Swoope's car to test his volume level, but with his setup it was so quiet it wasn't even worth taken out the sound level meter.

As a side note, the exhaust sounds phenomenal (albeit far too loud for daily highway driving) and the ExoticSpeed Cat-pipe has gotten rid of some of the raspiness that the Agency Power mid-pipe had introduced.

Again, I realize it isn't the most scientific approach so please keep the flaming the a minimum.

Race Roots

iTrader: (64)

If only all threads started like this.

Data we can compare

Good to see an improvement, but sorry you are not at your desired db level

Maybe we will see Swoope's Mid-pipe in action soon enough

Zeon

iTrader: (1)

Yeah I'm thinking it may be the AP exhaust itself as I mentioned, I'm considering tossing the stock muffler setup back on until I pick up a turbo.

636

Aww , i wanted an exoticspeed catless midpipe and agency power DR MP comparison. Thanks for this info though im sure people will find it useful . The dual resonated should be less raspy then the catless exoticspeed mp right?

Zeon

iTrader: (1)

What kind of comparison were you looking for? The DR MP was not less raspy than the ExoticSpeed.

636

Oh i was wondering if the catless exoticspeed had less rasp then the agency power dr mp. Was this comparison with the cat? If you were talking about catless , then im surprised by the results lol. I would've assumed the dual resonators would make the tone less raspy by far >_>. Would adding a header change the results?

Race Roots

iTrader: (64)

It was with the High Flow Cat and the AP DR Mid-pipe