1. we dyno'd before and after
2. we did street pulls. yes multiple ones. 40-110. 60-110. 40-140. i have video's of the car before and after. i've done tests with different downpipes and the ark exhaust. all were done on 3 vehicles which were all 2007 cobalts and i even have video's of the car on stock setup .vs. ark exhaust.
3. we even switched drivers just to prove that ark lost power.
Here are just some videos i put up. If you know who i am you would know i used to have about 200+ street racing video's on streetfire.net and have done multiple tests with ark, zzp dp's, and also injen cai vs the airbox mod.
test car 1: silver 2007 chevy cobalt ss/sc
test car 2: black 2007 chevy cobalt ss/sc
test car 3: orange 2007 chevy cobalt ss/sc
Before Ark Exhaust (silver balt vs. black balt)-
http://videos.streetfire.net/video/no-nitrous-2007-Chevy-vs_643889.htm
After with Ark Exhaust at night time + zzp catless dp (silver balt vs black balt)-
http://videos.streetfire.net/video/Two-2007-Chevy-Cobalt_644357.htm
silver balt vs black balt nitrous run-
http://videos.streetfire.net/video/Nitrous-Run-2007-Chevy-vs_643890.htm
Both Cobalts Nitrous Run *my jets were lower and a smaller shot than him (orange balt vs. black balt)-
http://videos.streetfire.net/video/Cobalt-wNitrous-vs-Cobalt_698691.htm I have pulls vs dan's car with out nitrous and even with nitrous that day. multiple video's.
Keep in mind I had to take all my video's down from streetfire.net. Only by request or certain times do i upload new video's anymore. I do have a bunch more video's of the silver balt and orange balt plus the black doing street pulls. Even a side exhaust dump test we tried and a whole bunch of other things. I've done the tests with multiple cars and dyno'd and even done street pulls so this is the reason why to this day i run the stock cat back exhaust on my car. I make well over 350whp/350torque on the stock cat back exhaust and i run CIA header + 3" catless dp.