Your question is why I posted the links at the beginning of my header build segment.
They include the theory of the principles behind the 180 degree design.
Here is where it has been discussed on the PIBB before.Lots of pics of installations here.
http://pantera.infopop.cc/eve/forums/a/tpc/f/5650045562/m/2460086584/p/1
In conventional cars most people use a X pipe to accomplish the same thing. Even out the pulses from bank to bank. George explained it well.
There are "Historically" correct designs as applied to the GT40 because the GT40 "Historically" used them. This involves making them correct in the materials used and the routing as based on the original race cars.
I imagine that there is a magic number that would be your engines optimim primary length but I know of no way to determine this other than Dyno testing different lengths.
As a rule longer pipes boost mid range and shorter ones boost top end.
The typical Pantera header is very short. 180's allow the ability to use a longer pipe.
I am going to push that limit when I build my under car set and see how long I can make them.
I am building both the 180 and undercar systems for my car and I will chassis dyno both to compare them but that is a long way off.
Did I mention that 180's look cool and I'm sure chics dig them.
