Regrinding crank questions

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ClassicComp
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Regrinding crank questions

Post by ClassicComp »

Possibly need to have a sbc steel crank 2.480 mains ground down to 2.300.
Will this need to be rehardened?
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Re: Regrinding crank questions

Post by Keith Morganstein »

ClassicComp wrote: Tue Dec 11, 2018 9:20 pm Possibly need to have a sbc steel crank 2.480 mains ground down to 2.300.
Will this need to be rehardened?
I’m sure it would be better to have it nitrided, but It’s been done countless times without.
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Re: Regrinding crank questions

Post by mag2555 »

That can be a uncontrollable process at times with good depth penatration at some areas of the Crank and only a few thousands in others.
I might look into getting it Cryogenic treated if the added cost is not a factor which would add strength that the Ni treating does not , plus have the added surface ware hardness.

The main thing by far though in terms of strength is to have the regrind put in a nice fat radius at the Crank cheeks and the mod the Main Bearings if need be for clearance.
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Re: Regrinding crank questions

Post by Momus »

Nitride for sure. The journals will be hard and wear resistant and the crank will be in compression giving extra fatigue resistance.
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Re: Regrinding crank questions

Post by Newold1 »

I would talk to someone who is a crankshaft builder and expert grinding and repair shop like Dave at Marine Crankshaft in Santa Ana, California and get the best opinion from an expert that does these things over the years in big quantities and knows what you can do and what will stay together the longest.
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Re: Regrinding crank questions

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^^^^^^^^Yup, Dave gets my vote too.
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Re: Regrinding crank questions

Post by Dave Koehler »

I have heard no mention of the intended application for this crank.
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Re: Regrinding crank questions

Post by ClassicComp »

SB2.2 drag engine
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Re: Regrinding crank questions

Post by Newold1 »

If that's your application then I and I am sure others here would recommend chasing down a good used aftermarket racing billet SB2.2 crankshaft . They are quite a few available at decent costs out of track racing team disposal in probably the type of journal size you are talking about.
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Re: Regrinding crank questions

Post by ClassicComp »

2.300 mains 3.625 stroke w/a BBC snout are tough to come across without a contact.
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Re: Regrinding crank questions

Post by Dave Koehler »

So...it's a blower application?
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Re: Regrinding crank questions

Post by ClassicComp »

Dry sump,ATI dampener jesel drive
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Re: Regrinding crank questions

Post by Dave Koehler »

FWIW, long before all the hi zoot cranks were available off the shelf like today we would grind the oem Chevy cranks down like you are doing and race on.
No issues to speak of and did not seem like a big deal at the time. Just sayin'
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Re: Regrinding crank questions

Post by ClassicComp »

=D>
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