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Old Jan 25, 2023 | 09:08 AM
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Default Engine Bored out
If someone takes a 1988 1340cc Evolution and has it bored out 10%, What does the size of the engine turn out to be? Is that 10% on each cylinder, or 10% all around?
Thanks, Bob
 
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Old Jan 25, 2023 | 09:49 AM
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Originally Posted by Blobis
If someone takes a 1988 1340cc Evolution and has it bored out 10%, What does the size of the engine turn out to be? Is that 10% on each cylinder, or 10% all around?
Thanks, Bob

Interesting question.....

I've never heard of someone boring out their engine 10%....

A big bore kit, or done yourself, is usually bored out to a goal in final displacement.... ie: boring an OEM displacement 80" EVO to an 83" or 88" displacement EVO...
 
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Old Jan 25, 2023 | 09:51 AM
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Are you actually meaning .010" maybe?
 
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Old Jan 25, 2023 | 10:41 AM
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a .010 overbore on an 80" nets you 82.2 c.i.d
 
Last edited by eighteight; Jan 25, 2023 at 01:48 PM.
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Old Jan 25, 2023 | 10:45 AM
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Engine boring is in thousands of an inch, .10 is a normal starting overbore. And then .20 .30 etc. up to the limit of the steel sleeve in the jug.
 
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Old Jan 25, 2023 | 01:40 PM
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Better put another zero in your figures above
Or you`ll be in the fins on an EVO
 
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Old Jan 25, 2023 | 02:35 PM
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Originally Posted by Tired

Are you actually meaning .010" maybe?



Damn, how did I not see that....

Good catch...
 
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Old Jan 25, 2023 | 07:32 PM
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Originally Posted by hattitude


Damn, how did I not see that....

Good catch...
Cali smog ?
 
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Old Jan 25, 2023 | 09:22 PM
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Originally Posted by back again
Cali smog ?

Nope, I was just stupid....
 
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Old Jan 25, 2023 | 09:40 PM
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Originally Posted by Blobis
If someone takes a 1988 1340cc Evolution and has it bored out 10%, What does the size of the engine turn out to be? Is that 10% on each cylinder, or 10% all around?
Thanks, Bob
Let's put it this way, aside from freshening up a tired motor you won't notice a bit of difference with that little of a displacement increase unless you bump the compression.

This case size really doesn't matter
 
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