C2 Coupe Exhaust and Choke Questions

[Dinger09]

Finally got around to the exhaust and found the mufflers had 2 1/2 inlets and 2" outlets. Is this correct? Should it be 2 1/2 in and out. Engine is the standard 327 300.

Documentation shows them purchased from ZIP in 1988 but the ZIP customer service guys were not much help. :confused

Also on the Carter AFB carb, the choke is sticking. Pulled it apart and the spring and shaft appear to be in good shape. The front butterfly shaft is OK also. Any suggestions other than just replace the choke.

 

[JohnZ]

ALL midyears had 2" outlets on the mufflers, regardless whether they had 2" inlets (base engine Powerglides) or 2-1/2" inlets (all others). Chances are the vacuum-operated choke piston (inside the choke thermostat housing) is stuck in its bore due to dirt/carbon buildup; remove the housing from the carb and clean it thoroughly so the piston and its link on the shaft move freely. An internal vacuum passage pulls air through that housing from the exhaust manifold heat tube all the time - the pressed-in tube in the manifold may have rusted out or become perforated, allowing exhaust gases (instead of just heated air) to be pulled into the choke housing.

 

[Dinger09]

Thanks John.