X pipe H pipe or side by side

This is exactly what I am saying. If the h pipe adds volume and it picks up HP, you either need a bigger primary tube, a bigger or longer collector, or a combination of any or all of those things.

Those x and h pipes are a band aid in most cases. Unless of course, you are trying to run down joe Gibbs for the money.

Funny thing is, I never see Comp guys or even most fast bracket cars don't use them. Unless they are required to use a full exhaust. Then maybe, because of rules, it would help.

As I pointed out, if the SYSTEM is correct, most likely you won't find a gain, and will probably find a loss.

Getting that system 'right' is a matter of a lot of track testing - and for the guys who race, it's definitely worth chasing it down. For guys building a street pounder, it will probably never happen.

That said, it's unlikely that a cross over will ever net a loss:
http://www.superchevy.com/how-to/exhaust/0505phr-exh/
"Based on such results, we can conclude that a balance or X-pipe is always a positive asset and never a negative." - David Vizard.

So it again comes down to intended use.