Unless you're planning to run some outrageous RPM, I doubt if you'll notice any problems at all. I've run the small-pipe ram's horns on 350's at 6K+ RPM on the dyno, and they could have handled more speed easily. The big ones (2 1/2" pipes) were used on the 300 HP 327's and some of the high performance 350's, and it was difficult to tell the difference in performance between them and most of the headers we ran during dyno testing.
Jerry


"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
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