85-90+?
#1
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From: St. Pete Beach, FL
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#6
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From: chicago
#7
The end of last summer I repowered my 1985 12 meter with all new natural 700hp/670tq running speedmaster 3's and 16.5x 25 3 blades and only hit 76. Now that was in flat water full of fuel at 5300 r's for just a few seconds here and there (still breaking in). My goal is to prop to around 5600 and throw a little chop under that heavy bi*ch and hope to pass 80, but im sure by not that much. Hitting 85-90 would only come with a broken gps or water powered speedo lol
#8
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Joined: Oct 2005
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From: Clarkston, Michigan
How come they are so slow? I'd be very disappointed if two blown 502s didn't get me 85 mph. I would definitely get the boat surveyed since some of the older Fountains are showing rot in the transom and stringers. Anyway it looks like a decent deal to me.
#9
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From: Cape coral, FL
It's not just about blown 502s. St about horsepower and torque. The straight bottom fountains take a little bit to get up on the pad then they run. A twin step boat is a different animal.
650 is easily attainable n/a so depending on build those motors may have a ton of potential to open up.
650 is easily attainable n/a so depending on build those motors may have a ton of potential to open up.
#10
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From: chicago
A buddy of mine had 650hp 502 with 250 blowers in his 38 straight bottom cig. It did 69-71mph.
My non stepped 38 with SSM drives and 800's, runs a tick under 90mph. These old hulls take some power to run honest good speed numbers.
Also, my 1990 38 is dry as a bone hull wise. But yes, any older boats you need to check for rot. I've seen it on fountains, cigarettes, formulas and donzis.




