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Is it a bad idea to use a lightweight crankshaft in a offshore boat?

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Is it a bad idea to use a lightweight crankshaft in a offshore boat?

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Old 10-30-2017, 04:29 AM
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I brought up this same conversation about 700 horse Small block nascar motors with Harold from Chief who now works with Ben who owns Precision Motors out of Grand Haven Michigan, by the way both Phenomenal engine builders and people.

Harold who is an Icon in this business Schooled me on how lightly built those lightweight nascar motors are built , and pretty much one unload-load off a wave would do it in.
I i have been really privileged to meet some great people in the boat business here the past year up in Michigan
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Old 10-30-2017, 05:31 AM
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NASCARs are built to last...about 3 hours. And once a Nascar gets airborne, they aren't usually worried about getting off the throttle for re-entry to the track, cuz they are usually upside-down.
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Old 10-31-2017, 06:00 AM
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I would think the lighter you make the rotating mass the worst it would be around the dock with a larger cam. Your not going to spin it to 8500 RPM'S.
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Old 10-31-2017, 09:05 AM
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i have never believed that the light weight cranks were the way to go,espically in endurance marine engines.
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Old 10-31-2017, 09:34 AM
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The Crower “Enduro” Crankshaft is designed for extreme durability and the cost conscious engine builder. It is commonly used in Pro Street, sportsman class, monster trucks, offshore boats, heavy nitrous and blown applications. Our proprietary premium grade USA Made 4340 "Non-Twist" Forging is the foundation for this crankshaft. This is the same forging that is use to make our Maxi-Light and Ultra-Light crankshafts. The only difference is the amount of machining and polishing time. This crankshaft features 1/8 radii, premium heat-treat processes, counter weight correct design and straight shot oiling. The Enduro comes standard with lightening holes in all rod journals. All rod & main sizes are standard unless otherwise specified. Specify rod length for proper counterweight clearance. Finish weight of this crankshaft will be 82-85 lbs dependent upon your specifications
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Old 10-31-2017, 09:52 AM
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I thought an old 502 kellog crank was bout 75-80 ??
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Old 10-31-2017, 11:39 AM
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We would “blade” our superbike cranks to cut through the oil bath better but also mostly for better acceleration shooting out of the corner faster. With 10-20 corners a lap that can be helpful, but a funny consequence is that sometimes we lost acceleration grip on tire because the lighter crank didn’t tame the engine pulses as well and was a palpable result on the track. These are on 1Liter/200hp engines turning 14k rpm. A lighter crank in a boat with a bravo drive is the wrong direction, lol.
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Old 10-31-2017, 04:59 PM
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Originally Posted by tommymonza
I i have been really privileged to meet some great people in the boat business here the past year up in Michigan
Ahh thanx man, that really means a lot

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Old 10-31-2017, 05:06 PM
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Originally Posted by ICDEDPPL
Ahh thanx man, that really means a lot

Do we need to start a Avatar fund raiser for you so you can reup your membership......... ( . )( . )
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Old 10-31-2017, 07:09 PM
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Originally Posted by fbc25el
I would think the lighter you make the rotating mass the worst it would be around the dock with a larger cam. Your not going to spin it to 8500 RPM'S.

I agree with you on this. Similar to light weight flywheels. I see where MT is coming from but endurance like mike said I'd stick with the norm and not chance it. Some say lighter cranks are easier on rotating assembly. The little bit of hp increase wouldn't be worth it to me unless it's proven. Not sure in a boat if light weight crank would effect deceleration like aluminum flywheels do or not. I'd let my machine shop reduce weight where they can while balancing without effecting the strength. I like the 8 counter weight cranks and so does my machine shop. Understandably why.... Makes balancing much easier.
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