How much can you bore?

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May 23, 2007 | 03:26 PM

J Wikoff

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How much can you bore?

How much can you bore out a SI? I'm thinking about what to do with my old engine.

May 23, 2007 | 03:32 PM

bandit

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From: NEBF:06,07 | NYBF:06,07 | ONBF:06,07 | CNBF:06 & more............

didn't Sqela do this to his when he rebuilt it because he scratched the walls... :?

i think he knows.

May 23, 2007 | 03:34 PM

Rogue

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From: Westerville, Ohio 2000 Black SSEi

It will depend on the amount of core shift but on the series II motors we typcially see anythign beyond .030 as being dangerious however we have gone as far as .060 on a motor and it was sonic tested good.

May 23, 2007 | 03:40 PM

J Wikoff

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What does dangerous mean?

May 23, 2007 | 03:43 PM

BillBoost37

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It means the cylinder walls are too thin to handle the load imposed by the compression and explosion of the charge. As well heat is a large contender.

May 23, 2007 | 03:49 PM

J Wikoff

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So it will deform or blowout?

May 23, 2007 | 05:26 PM

ReallyAGXP

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From: Somewhere south of Ottawa with your girlfriend driving faster then you.

try it with your luck... What do you have to lose... lmao

May 23, 2007 | 05:43 PM

Greyhare

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From: Purgatory

It would most likely distort and have excessive blow by.

In an extreme case I guess you could get cracking in the cylinder wall.

May 23, 2007 | 09:46 PM

sqela

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Quote:

Originally Posted by Rogue

stick to .020 on the series I

when I first was planning the rebuild I was aiming for .030 but was advised to stay to .020 by my machinist who has been doing engine blocks for over 30 years