Originally Posted by 94gtconvert
Today I installed a pypes 3" x to my existing off road 3" cat deletes. The factory h was something like 2.75" I believe and was hands down louder in the low rpm range. But after installing the x I feel like it's quieter from 1k to 3,500k rpms, and I feel like I lost bottom end power. However it feels like it's pulling harder from 5k and up. I don't get it.. I don't see how a mid pipe can make that much of a difference. Am I going crazy or does a mid pipe really make a difference on the coyote..
X pipes will always be a little quieter than H pipes because the exhaust pulses are forced to intersect at the X junction. Some sound waves will crash into each other at the junction and cancel out. It has the side effect of acting like a mini muffler. This is why the X pipe setup is perceived to have a smoother sound by some than the H pipe.
I did back to back testing on my previous vehicle, a Procharged 5.4L F-150 with full custom exhaust. Divorced true duals, custom X pipe, and then custom H pipe. The Divorced true dual system was the best sounding/loudest but probably not the most efficient since it had no crossover. I noticed the X piped system was immediately quieter and lost a lot of raw tone to it, but it was smoother sounding. Lastly, the H piped system sounded like a compromise of the previous two, gaining some of the tone back.