Running a H Pipe,whats the advantage

I have a TTI 3" X-pipe installed as close as possible to the collectors, which is just in front of or just behind the trans mount (I'm forgetting at the moment, but probably behind), on my race car with it ending at the rear housing with Dynomax Ultraflows.

I couldn't do same day back-to-back tests, but my records show that it helped reduce ET's, especially after leaning out the carb a couple of jet sizes and taking out the 60 lbs the system added from elsewhere in the car. It appears to have helped me a minimum of .05.

I have also gotten a lot of compliments on the sound from open header racers at the track. But I can still hear my noisey electric Holley fuel pump inside the car while at idle!

H-pipe may help but X pipe works better if you want to do the extra work to fit it in.