X & H pipe vs straight dual exhaust
Sorry, just giving you a hard time. Can you give an example of the good X pipe?
its a hard one realy, most you find in a box made out of mandrelbends would be ok if they just got two things right about them.
one thing that sucks with alot of them, the monkeys that make them rarely debur the cuts before final welding wich looks like crap and might create alitle turbulence,,its also quite comon to see that noone took the time to match the two sections togheter giving what i consider another chance of turbulence with the two openings cut out of the bends not fit togheter right.
i used to make x-pipes and created a design for the company i worked for without much actual testing but with good craftsmanship and pride in makeing the parts fit togheter right.
in the very simple backyardstyle testing i did i found that you dont realy need a very big hole betwen the two tubes to create a strong pull thru the opposing tube. it was mostly about attention to detail on the cuts realy. im sure welmade parts from some brands makes slightly more power due to more scientific testing but just attention to a good fit betwen the parts seem to be what is important and i would avoid cutting out to much since there realy isnt a point in doing so.
for simplicity compare TTI X-pipe for an abody to alot of the cheaper universals and you will get a pretty good idea about basic differences in cutting the bends.
i also like to use less than 90 degree bends for neat packaging under the car and less restriction. with the front section being wider spread than the rear section.
avoiding to get into to much details to avoid any trouble with my previous employer (its not TTI or any of the big american brands) that im still on good terms with and want to keep it that way and considering the possbility this somehow managed to get trademarked or similar since i left.
hope it helped a little hard to explain in text.