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Stroker crank and case borking question

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What would the displacement be of a stock 103 with a S&S stroker crank? My guess is a 113. Is case boring necessary to fit a larger cylinder or for clearance for a larger crank? This is for my general knowledge. Thanks as always for your help. :smile:
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Thanks. I just saw I wrote case borking. lol. Is the case boring needed to clear the new stroke?
Since I have my current build figured finally I'm researching for when I have to rebuild. Hopefully not soon. It seems that the crank is the weak link so when rebuild time comes at 200k (lol) I can do a total rebuild. It looks like S&S is the way to go with a crank. I'll probably go with a 4.625 crank and have it welded for extra security. I like that you can just bolt on an extra 14 cubes but how much is too much before you compromise the crank shaft? I'm looking for usable torque not drag racing rpms. I appreciate everyone's help and advice here. I'm learning and I'm having fun with it.
Thanks Joe. That may be the direction I head in eventually. Right now I'm learning and seeing what works and what doesn't. I love to ride but I also like to know how the nuts and bolts go together. The whole process fascinates me. I haven't built a motorcycle engine yet but I have done a few V8s in my time. I can't wait to get my hands in there. Thanks again.
I just like to do my own work because I like knowing what I put in there and it's therapy for me. Although all the obsessing I do prior to a build probably offsets the therapeutic value. :grin:
Without boring , the 103 is a 4.375" stroke

a 4.500" stroke is a 106

a 4.625" stroke is a 109

boring to 4.00"

stock stroke is a 109

4.500" stroke is a 113

4.625 stroke is a 117

increasing one or the other .125" yields around 3 c.i.

HarleyJack could you post me some numbers for the 4 1/8 cylinders and pistons. I swear I look at these numbers you posted about every other day. Thank you for your time.
Thanks for the info. What are they using to get the 143?
How'd you break the spindle? There has to be a story there. Most of mine start like, "Hey y'all watch this!" :grin: it sucks that it broke and they won't warrantee it.
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