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nicajmar
07-18-2011, 08:45 AM
I need a Alpha 1 outdrive for a 86 18 Classic with a 300 Tempest. Does anyone know what gear ratio it came with? Is that the ratio I should replace it with or does another work better? Its was spinning a 21P prop , should I be able to go to a 23 with that set up? Does it matter if I put a Gen 2 Alpha on it?
Lastly does anyone one on here have a good used Alpha for sale that will work for me?
Thanks Tony

Donziweasel
07-18-2011, 09:46 AM
Tony,
The 300 Tempest was a high performance engine produced by Mercruiser from 1985-1986. It was around 300 hp, but most think this was a little overstated and was around 270. An Alpha with a 1.5 ratio should be perfect. Welcome aboard.

gcarter
07-18-2011, 10:47 AM
I don't think you can easily bolt up a newer Gen II outdrive to an earlier Gen I gimbal assembly.

MOP
07-19-2011, 07:04 PM
PM Rootsy he has done that upgrade, he can tell you what you need to do. About the 300 Tempest/Alpha package my 22 came that way it would swing a 21 heavy cup to a tad over 61mph. It had a much better cam was a 4 blot block with good rods had a very pronounced lop, I think it was rated about right.

a.casolini1968
09-12-2011, 06:27 PM
My 1986 Kavalk 19 came with this package.Glass deep Vee hull mahogany deck 2700 lbs 23 degree Levy type bottom,71 mph 23 ' pitch at 5150 at 2.5 " X dim and 75 mph with 25 " pitch on Alpha SS at close to 5" X dim. Did not look at the tach.My point is that the Tempest has more than 300 HP and does it ever sound and run sweet.My 2004 22 C runs Bravo with 6.2 barely touches 60 with 23 " pitch .But then the A/V plate is only 1/2" above the keel