I would thing that if "someone" offered a big tube shorty that you'd see that power and torque gap between shorties and full length headers get even more narrow. If you notice, all the shorties offered are small tube. If someone made say a 1 7/8 for a small block and a 2" for the big block, IMO it might level the playing field a little. Also most shorties only have a 2.5" collector. Plus, there's room to do it! You normally only run into header clearance issues with bigger tubes with things "down under" the engine bay, like torsion bars, center links, tie rod ends, pitman and idler arms. Shorties eliminate all of those issues.
