Well, I think the original were 2" (I think), so that is probably what Alan's are also. The chamber diameters are 3", but the inlet/outlets are only 2" (again, I think that's what they are...I am too lazy to measure ours and see!). The worst part is where it flattens under the cross member and right before and right after the last chambers.
I am kind of undecided if we should keep our chambered, or get the "correct" dual into transverse muffler type exhuast. I'm not sure which one would yeild better performance
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