[chopper]

Going on four years ago, I replaced my old pipes with a set of the "ceramic mat" sidepipes from Stainless Specialties. Before I sent in my check, I talked with a gentleman from New York who had actually tested both of the Stainless Specialties types (baffled vs. ceramic) against open headers on a dyno. For info, his car was equipped with (I believe I recall correctly) a stock dimension 427 running dual Holleys. This gentleman kindly sent me copies of the test run sheets. Bottom line: the delta between the open headers and the ceramic pipes was only a few hp and no difference on noise level, while the difference between the baffled pipes and the open headers was on the order of 45 hp and a noise level difference of about 5 dB. Noise levels were measured at 20 feet from the end of the pipes. My conclusion from his data was that the baffled pipes cost a lot of hp for not a lot of muffling (at least on the big block FE), so I went with the ceramic pipes.

FWIW, the wife and I use ear plugs when we ride. I have always worn ear plugs while flying (going on 30 years in helicopters), and have found that the EAR brand yellow foam plugs seem to work the best.