I need to replace 1985 5.7l Mercrusiser I/O engine. I have been considering a Goodwrench GM crate light truck engine (dressed long block) LM1 (new, about $1400 shipped) vs remanufactured marine 350, about $1800 shipped. Besides the cam differences, SS head gaskets, brass freeze plugs, are there any other significant differences? If the boat is used in fresh water only, are the brass plugs and SS gaskets necessary. I realize the GM truck cam is somewhat different from theOEM and GM Marine cam (Intake lift/exhaust lift .383/.401 for LM1 vs .442"/.465 for marine, and 194deg/202 at .050" duration for truck vs 214/224. Are these cam differences significant? It seems to me that buying the crate engine and replacing the cam is the best choice. Any advise on others experience with truck engine swap and cam suggestions is appreciated. Hate to be so long winded - thanks in advance for the help.
