Dave Grote
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Have anyone bored out the center of a crank for more flow, Looking for some input on how to do it
Cranks
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dwilfong
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I did it one time and will not try it again. Used grinding stones on a dremmel tool . found ones the size I was looking for and had at it.
It took for ever and a bunch of stones.
Not worth the effort if you ask me. unless you have the right stet up to grind it the right way.
It took for ever and a bunch of stones.
Not worth the effort if you ask me. unless you have the right stet up to grind it the right way.
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You may break it quite easily >
BRAD
BRAD
PaulHail
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Dittos. You're asking for crank failure if you bore out the center of a crank.
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What size engine are you trying to bore out?
I have done a few 21 size car engines. Used a straight flute carbide drill then a small boring bar. The boring bar was tricky due to small size and wanting to chatter.
Mike
I have done a few 21 size car engines. Used a straight flute carbide drill then a small boring bar. The boring bar was tricky due to small size and wanting to chatter.
Mike
Dave Grote
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It is a 21Outboard crank from France
bermudadude
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- Feb 3, 2003
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decades ago that was ur only choice in addition to other mods. breaks ALLOT quicker. now days u get a 14mm crank in any engine worth mentioning and the hole is large enough. 10mm or so hole and a 9mm carb then the only other thing would be to change the timing (thats another thing that can make it break faster than stock) have to be carefull to round all the corners
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