283 small journal questions

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AuroraGirl

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Are the bore the same.. wouldn't a head with a longer stroke decrease compression?
 

custodian

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Are the bore the same.. wouldn't a head with a longer stroke decrease compression?

283 standard bore is 3.875 with a 3'' stroke. the 350 standard bore is 4" with a 3.48" stroke, and the 400 is a 4.125" bore with a 3.75 stroke. The longer stroke gives more torque. The smaller the head chamber, the higher the compression ratio, which would vary upon the size of the bore and piston type, example: dish, flat top and dome pistons would give a different compression ratio with the same head chamber.
 

AuroraGirl

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283 standard bore is 3.875 with a 3'' stroke. the 350 standard bore is 4" with a 3.48" stroke, and the 400 is a 4.125" bore with a 3.75 stroke. The longer stroke gives more torque. The smaller the head chamber, the higher the compression ratio, which would vary upon the size of the bore and piston type, example: dish, flat top and dome pistons would give a different compression ratio with the same head chamber.
Oh, okay, I dumbed out for the second. THe piston cant cross the head gasket, it would destroy it. So it can mis match? Interesting. Would it work without any modifications
 

custodian

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You can't put 283 pistons in a 350 or vice versa, and the cranks are different, 283 small journal and the 350 is a large journal. You can take the 283 you have and put it in your truck, will bolt right up. The accessories you would have to work out.
 

AuroraGirl

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I meant the 305 option you mentioned
 

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