FE Power Forums
FE Power Forums => Non-FE Discussion Forum => Topic started by: Stangman on March 15, 2026, 09:45:52 AM
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Was looking on Scats website and thought it was odd that the lightweight cranks are cheaper than the regular cranks. I would think more machining on the lightweights. Obviously there out there but they don’t list a 4.375 crank. Is it a special order.
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Yes 4.375 is custom.
Lightweights are cast cranks, 9- part numbers, and the forged are 4- part numbers.
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Where did you see the prices? The steel Superlites are generally a lot more expensive.
Scat has went through some drastic price changes lately, maybe some venders havent caught up.
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Right on website. Cranks, rods , rotating assemblies and more. Regular cranks like 1400 and lightweights 795. Big difference
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Ross is correct.
In the SBF world, there is a lightweight and superlight. Not in the FE world.
So what they're calling a lightweight FE crank is actually a cast crank.
Cast cranks are lighter than forged cranks, so technically they're correct, but it's kind of a misnomer because they have other crankshafts available with other families with "lightweight" and "superlight".
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If you go on the website they show a picture of both cranks and there is a big difference. You can see the difference easily. But being a cast and it definetly is thinner in some spots looks like if it was a high horsepower motor I guess it’s possible it could be a weak link.
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Safe power limit for the Scat 4.25 stroke cast crank?
Would it be good to say, 650 HP?
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The common opinion is that in an FE, they can take a lot of power, some guys say well in excess of 700 hp
However, keep in mind, overall component balance (from balancer to clutch and everything in between), heavy/light parts choices, RPM, and even main design all matter. A cast crank doesn't flex it breaks. I tend to be a much more conservative. it's a decent chunk of money to move up to forged, but how much for a broken block?
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I have sold - and built - hundreds of FE engines with cast Scat cranks for over 20 years now.
I have only had a few of them truly break.
They were at or over the 700 HP level, or in continuous load applications - marine/road race.
Those guys - along with blower guys - simply require steel. No option.
For everyone else it's insurance.
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My rough rule of thumb is if you have an aftermarket block, go ahead and snag a steel crank. Otherwise, in a lot of cases, the cast crank will live longer than a factory block will.