Trombone Exhaust

Evening All,
I'm trying to find some info on the Trombone.
I've been involved in all sorts of motorsports and understand the philosophy behind a performance exhaust system.
The original "Y" pipe that was used on most homebuilts is known for being a HP thief.
Does the 270* of bends eliminate the open exhaust from firing into the open intake?
Thanks in advance for the lesson.

Mark

The story, and reason for why we came up with the trombone exhaust is rather interesting; mainly the need for mufflers on the forward facing cold air sumps to comply with European noise restrictions, and provide better cabin heat for cold climates.
The “trombone” idea is really nothing more than separating exhaust pulses with more tubing length, which is what the crossover does, but in a different way.
The rear cylinder exhaust (4&3) do go through some tight bends, about 160 and then a 120 degree bend, which is a tight radius. Based on the testing that Larry did, tight radius bends aren’t a restriction factor as we once tested an entire system built entirely with very large radius bends.
Hopefully this information helps, and feel free to call if you have questions.
Clint/Vetterman Exhaust 605-891-1290