Chrysler 6 in. Exhaust Riser | Barr Marine CM-20-6674 Designed for Chrysler small block marine engines with log style exhaust manifolds to get exhaust higher than water line of boat. Barr Chrysler 6 in. exhaust riser Used on Chrysler LM318, M340 and M360 engines from 1968 to 1985 Includes mounting hardware, gaskets, and plugs Heavy duty cast iron Painted Chrysler blue Replaces Barr CM20-6674 Replaces for Chrysler 2846689