What Is A Formula 'S' Package 'Year to Year'

Rocky_JS said

I didn't think they used an actual muffler until 67? The 65-6 model used only the resonator? In 67 it had both muffler and resonator w/273 commando option.

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Rocky-JS,

In 1965, the 273 High Performance did come through with a Muffler {Straight Thru Design}.

But, it was a 'hollowed out' Muffler, for low back-pressure and low-restriction.