For anyone interested here is a dyno of Pro-1 non-resonated test pipes. It was done on a stock exhaust with a stillen intake, z-tube, and the MREV PLUS. Sorry I could not get a baseline with just the test pipes. There is only one run because the rest of the runs were within 1 or 2hp and some had weird dips and spikes. I am not sure what happened under 3k, seems like maybe I reacted a little slower this time when I was told to floor it. I do not feel that much of a loss of power under 3k. The car is a little more raspy around 3k on and it kind of sounds like an open wastegate, just not nearly as loud. There is a gain of about 6hp at the peak with smaller gains throughout the powerband. I can't feel the difference because quite frankly who can feel 6hp? The second graph shows my baseline with the stillen and z-tube, the MREV PLUS next, and then the test pipes.

 

Good info. Your dyno graph did what mine did as well when I installed the MREV and had a before and after Dyno. I dunno if the car is freaking out for some reason or another but it showed a loss before 3k like that. But the car is definitely stronger period. How much were those test pipes?

By any chance you get a air/fuel reading?

 

Got them from our private classified for $50. NO A/F reading. I get the dynotime at a lowball price so I don't use their wideband. I will only use it to tune A/F maps.