Tom,Funny you should bring up aluminum and Salt water.I know this from experience.The smaller Berkley Jet drive 17 Foot Sutphens/Donzi Speed Boat they pull the outside water source to propelle the boat and cool it.So if your running your boat in the Lake or river no salt water.Yes if you run in the Bay or Ocean you have a very high concentration of Salt in the water.Correct me if I'm wrong but their were very few Flat Bottom 17/18/19 foot Jet Drive Speed boats in the Chopping bay or open seas,these boats needed calm conditions to go fast otherwise the waves would flip them.I tried my 17 Foot Sutphen Flat Bottom Speed Boat once down at the Jersey shore in the Bay,Boat hated the big wakes,couldn't enjoy it.This boat had a 427 4 bolt with aluminum GM heads Wiend 671 GMC Blower,Nasty Radical solid cam,2 Holley 750 CFM double pumpers,Vertex Magneto,Hooker Chrome Headers etc...Motor Built By Tony Fiel in Raritan NJ.Yes As soon as I pulled it out of the bay I hook up a hose to the back and flushed out the motor real good.Boat was Black Lacquer and said "Jaws" on the back.Not sure if the Bigger Ocean V-Hull Speed Boats use the outside water source to cool their engines,maybe someone can answer that Question.As far as Smokey goes how much concentrate did he actually use,did he flush the motor after racing?