1957 Corvette: Service Bulletin: Spark Plug Replacement
Model Year: 1957
Subject: 1957 Corvette Spark Plug Recommendations
Source: Chevrolet Technical Service Bulletin
Bulletin Number: DR #295
Date: May 22, 1957
TO: ALL CHEVROLET DEALERS
Inasmuch as the grater percentage of Corvette engines are being operated in traffic congested areas AC-46 Spark Plugs are now being installed in production.
AC-46 entered production 4-9-57, Serial number E57S103268.
Corvette Engine Spark Plug Recommendations
|Type||Type Driving||Part No.|
|AC-44||Town & Country||1559492|
|C-43 Comm.||Heavy Duty & High Speed||5612002|
|C-42-1 Comm.||Road Racing||5612140|
Above information will be inserted in the Corvette Operations Manual and will appear in next edition.
Corvette Engiens with AC 46-5 Plugs
170 Corvettes wewre built during period 3-29 to 4-9-57 with AC 46-5 Plugs installed.
Serial # E57S-103098 to 103268.
These plugs should be changed to AC-46 due to spark plug boots not fitting the AC-46-5 plugs properly.
In cases where units operating in heavy traffic continue to oil foul spark plugs oil shedders should be installed.
Manager, Serice & Operations Dept.