Thread: 3 vs 4 cylinder
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Old 09-16-2008, 03:31 PM   #25 (permalink)
metromizer
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Quote:
Originally Posted by guitarterry View Post
can anybody tell me what an offset grind using oversize bearings (easy to get) would give me in displacement loss.
You really want to go at it from the other angle...

bore and stroke numbers will give you displacement. rearrange the math such that you fix bore and 4 cylinders, and the answer spit out is new stroke.

You can't pratically get away with any adapter bearings or oversize... the ones available are in very small increments only suitable for repairing a damaged journal, not destroking.

Offset grinding a crank is accomplished a couple different ways:

prep and submerge arc weld the journals ,<build up>, grind, stress relieve, straighten, re-nitride the journals, balance, (I probably missed a step or two).

Many times you can find another rod that uses a smaller bearing journal size (Honda journal is real popular right now with race engine builders). Smaller enough that you can offset grind the crank without adding any new material.
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