Are all years 911 SC exhaust the same?

[rjrandalls]

Have the opportunity to replace my '83 911 SC exhaust. Will unit from 78-79 first year for SC fit the '83 model year? Anybody?
Thanks!

[30westrob]

Your 83 SC heat exchangers have thick/ tall flanges, using long head studs. Early SC's used thin flanges with normal head studs. To use early heat exchangers you need to replace the long studs or use spacers. Rob

[RarlyL8]

The USA 78/79 SC were Euro engines modified for the US market. The older exhaust system will fit the newer engine but may have a premuffler instead of a catalytic converter. Spacers are recommended. The later model exchangers will not fit the early model engine due to the stud length as stated above.