X pipe vs H pipe

I've posted this in other threads, but I guess it can go here too!

I ran TTI 1 5/8"-1 3/4" step headers with collectors on my car for a year or two, tuning the carb as well as I could. I then installed a 3" X-pipe ending with 3" Dynomax Ultraflows at the rear axle housing. After removing the 60-70 lbs the exhaust added to bring the overall weight back down to what it was, and tuned on the carb a lttle bit, the end result was faster ET's by .05 -.10 - on my particular combo.

I'm sure the X-pipe helped and that the mufflers didn't hurt. I also get a lot of compliments at the track, and it certainly doesn't sound like an Italian sports car.

Your results may vary. But as with most engine related changes, adjusting the jetting and sometimes squirters is needed to get the most out of that change.