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Crank counterweights most likely will have to be turned smaller, they nearly always won't clear the pin boss in the piston at BDC with a 5.85" rod.

Call whomever made the crank you have and ask if it will clear with a 5.85" rod, they will know.

If you do end up turning the counterweights undersize, note that is isn't a simple straight radius cut, it is an offset cam cut. If cut round you take out more weight than they can put back with mallory for balancing and the crank is then junk.,
That work plus the amount of mallory metal that will have to be put back in to get it to balance may just cost you as much as just buying the right crank to start with new, plus you can recover some by seeling the crank you have.

I asked SCAT a whie back about putting 5.85" rods on their 6.0" rod SBC cranks...no go out of the box, not without an expensive rework and mallory slugs. Counterweights will not clear the pistons at Bottom Dead Center.
 

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can you explain alil on the stroke
Not really, but I suppose if a guy tried hard enough to design a piston, and rod assembly, and ring package it would be possible to pull the piston down past the point of no return, on purpose, it could happen. I truly have never given it much thought, to be honest with you, but I always ran short strokes, with the lightest piston, and tight ring package I could run. On a 9” deck, I don’t see any problem with a 4” stroke having a real problem, but I ain’t an expert on it. On a 5.85 rod, when they’ve ran the 400” sbc with a 3.750 stroke, and a little shorter rod then 5.7. I’m sure a lot will depend on the piston design. But it would have to have a pin pretty high up with that rod.
 

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Crank counterweights most likely will have to be turned smaller, they nearly always won't clear the pin boss in the piston at BDC with a 5.85" rod.

Call whomever made the crank you have and ask if it will clear with a 5.85" rod, they will know.

If you do end up turning the counterweights undersize, note that is isn't a simple straight radius cut, it is an offset cam cut. If cut round you take out more weight than they can put back with mallory for balancing and the crank is then junk.,
That work plus the amount of mallory metal that will have to be put back in to get it to balance may just cost you as much as just buying the right crank to start with new, plus you can recover some by seeling the crank you have.

I asked SCAT a whie back about putting 5.85" rods on their 6.0" rod SBC cranks...no go out of the box, not without an expensive rework and mallory slugs. Counterweights will not clear the pistons at Bottom Dead Center.
This right here may be the best information.
 

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Discussion Starter #25
I'm sure someone has done this, Now i'm curious as to the benefit's if any. This topic is purely for knowledge, not trying to be hard headed.
 

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Someone has done pretty much anything anyone can do with a small block Chevy.

If you decided on the 5.850 you can get a decent ring stack with the oil ring in the pin hole. It's also easier to do a dish if you need to go that route. You can also use .043 - .043 - 3mm rings (or whatever) and pick a bit of room up there.

Always remember that "nitrous oxide is the best thing that ever happened to piston manufacturers"....and go with a turbo. It will probably be cheaper in the long run.... :D
 

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Discussion Starter #28
This right here may be the best information.
Thank you was really good info, I called callies, I sent them pick of the crank, they said it shouldnt be a problem, but to still get it check, I will. Thanks again for the knowledge.
 
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