Showing the difference in length between 68-69 manifolds and 70-74 manifolds side by side

Choosing the Correct Option for 1968-1969 and 1970-1974 C3 Big Block Side Pipes

by Ryan Westdorp on January 19, 2023 Categories: News

For the sidepipes we manufacture, the biggest difference between 1968-1969 and 1970-1974 C3 big block Corvettes is the placement of headpipes: the headpipe on the driver side moved about 4 inches away from the oil pan for 70-74. At the same time, there was no change on the passenger side.

On each C3 sidepipe product we offer there is an option to select your manifold size - for all big block C3 sidepipes, you’ll see a 68/69 big block and 70/74 big block option.

If you’re ordering sidepipes for a 68-69 427 big block, the left hand manifold casting must be #3880827. If you are ordering sidepipes for a 70-74 454 big block, the manifold on the left hand side must be #3969869 for the headpipe to correctly fit.