I'm pretty sure people have dynoed our neons without a resonator and there is no difference in power. Just sounds different.

 

well mine definatly ran different. low end torque was down because i couldnt even chirp the tires off the line. on the high end i think it actually ran a little faster though. but how often am i gonna be driving down the street doing 80 right? well, when i put the cherrybomb on, i got my torque back. so im sure there will be a dyno difference whether you have backpressure or not.