My notes for setting up Dutra Duals says 2" pipes from the engine into a wye, 2-1/4" from the wye to the muffler (a Walker quietflow), then 2" to the tail of the car.
there you go, they dont mention the length of the head pipes? Strange....
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"...Pete Hagenbush (sp?) was one of the engineers who helped develop the 2 barrel Super6. In an article in Allpar talking about the /6 he said splitting the exhaust in two, 1-2-3 and 4-5-6, running 2 pipes back about 6-8 feet, then re-joining them into a single exhaust out the back made a lot of power. He wanted dual exhaust on the Super6 but it was not done because of the cost..."
KosmicKuda Slant six dual exhaust proposal
