I came across a 1979 18' Marlin Tiger Shark with a '79 Merc. I6 140 on it for sale. This is a boat that has always intrigued me, and I was considering buying it. <br /><br />In case you don't know, this boat is a low profile, ski boat (NOT a Tahiti style boat) that you would often see back in the '70's and '80's with a V8 v-drive powering it. Marlin, Advantage, Kona, Avenger, etc. all made versions of this same low profile, 18' ski boat.<br /><br />I would expect a boat like this - if the engine were running right - to be about a 50-55 mph boat at top speed. It turns out that the guy selling it told me the best performance he gets out of this thing is 5000 rpm with a 17 pitch prop, doing about 40 mph! This seems WAY off to me! It sounds about right to me if that 140 were actually a 90 in disguise. What do you all think? Thanks for any help.<br /><br />TG
