i think the 2 and 3 chamber are both "delta flow" because the insides have a triangle type baffle system (delta has something to do with triangles, but i don't exactly know what), the difference the 3 chambers have one more baffle chamber. I may be wrong on this, but this is what i assumed. I garauntee if you get an offroad h-pipe (no catalytic converters or dimpled bends to disperse/dampen the sound waves) you'll be able to wake up the dead, or at least your neighbors.
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'84 Mustang 5.0 LX
My car