What is the diff. in hp/tq rating between mid-lengh headers and longtube headers? Let say the bassani mids vs. arh longtubes.

 

Peak power is irrelevant IMO. Your going to be recieving a boost in hp/tq, and pipe length/diameter will only heavily impact power range and sound. Its safe to say lt's will offer more low end torque while mid-lengths will offer a littlemore hp higher up. I would recomend mid-lengths if you've got the money, but your stuck with that companies mid-pipe only and lose a little customization. lt's would be cheaper and have a larger mid-pipe market.