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Best prop for tantrum with stock 454 mag with 365hp

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Best prop for tantrum with stock 454 mag with 365hp

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Old 03-22-2012 | 09:18 AM
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Originally Posted by Gladhe8er
Where do you boat in LI Sound? That's where I run mine, out of Norwalk, CT.
We run out of old saybrook
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Old 03-22-2012 | 10:30 AM
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Originally Posted by carreraboy1
We run out of old saybrook
I get up there once in a while. I'll hit you up.
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Old 03-22-2012 | 10:35 AM
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Originally Posted by carreraboy1
Hey guys I want to get some input on what prop to go with. Last year I ran a 21p 4 blade which gave me a good mid range speed but on got around 4200 rpm out of it. Any other suggestions? I do most my riding in the LI sound so looking for something that is best for rough water.
So if you do have the mag motor just know you NEED to run it within the specified rpm range of 4600-5000. The motor was built with this in mind and its not good to run it at 4200 if that is WOT. Personally, I think you are going to need a 19p Mirage + prop based on your numbers UNLESS your drive ratio is something other than 1.5
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Old 03-22-2012 | 11:18 AM
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We run out of old saybrook...
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Old 03-22-2012 | 11:19 AM
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Any suggestions on how I can tell for sure that it is a Mag or not?
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Old 03-22-2012 | 12:48 PM
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If it has an aluminum high rise intake, its a mag engine. If it has a cast iron, flat intake, its a 310 or 330.
Assuming that somebody didn't swap intakes.
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Old 03-22-2012 | 04:45 PM
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Is there any other way to tell because I am not sure if the manifold is stock or not.
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Old 03-22-2012 | 04:54 PM
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Remove a valve cover and if it says "PASS" stamped on the head its a 330hp...If it says "HI PERF" it has the square port heads and is the 365hp mag motor.

Also, look at the sticker on the drive--do you have a 1.5 ratio? Your boat weighs approx 5000 lbs wet and should be able to push a 21p prop to more than 4200 rpm's (even if you have the 330 hp 454). Either your boat has gained alot of weight, your tach is off or your drive ratio is not the standard which would be affecting rpm's.
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Old 03-22-2012 | 05:04 PM
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Originally Posted by ActiveThunder
We were not aggressive with the X-dimension back then. You need to go back to a 3 bladed Mirage. The pitch would have been a 23.
One more time and then I give up.
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Old 03-22-2012 | 05:14 PM
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Originally Posted by ActiveThunder
One more time and then I give up.
Probably should listen to this guy, considering he built it....
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