I seem to remember the pivoting ball being used along with a spring-loaded flange to allow the pipe(s) to pivot a little as the engine rocks on a somewhat soft motor mount. It's seen pretty often on transverse-mounted engines that rock back and forth from torque reaction during acceleration. Older designs tried to keep the connection between the engine and the pipes more rigid.
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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