H pipe v X pipe?

Thats an interesting read.

Now down the road, I will be looking at adding a better intake manifold such as the Performer RPM or Stealth, shorty headers witha dual exhaust and possibly the Flowmaster 50 mufflers. Would also like to replace the stock C4 tranny with an AOD and add 3.25 or 3.55 gears in the rear end.
So I'm not looking to make a street killer by any means but want it to be quicker than it is now.